Introduction To Computers Module

 

 

 

1.0 Course General AIMS 1.1To provide an understanding of the operation of the hardware of a computer system and the roles played by the unit of the system. 1.2To provide an understanding of the software of a computing system and its interaction with hardware. 1.3To introduce the students t of basic computer care and maintenance. 2.0 

Objectives 2.1Identify and describe the operation of major hardware units of a computer system. 2.2Describe the operation, characteristics and application of typical bulk storage devices. 2.3Identify and describe the duties and responsibilities of computer personnel. 2.4Describe the arithmetic and logic operations performed by the computer. 2.5Describe the architecture of different types of computers. 2.6State the requirements of a computer room environment and describe the security measures required for the computer room information.

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3.0  Contents 3.1 Computer department and functions in a company

Pages 7 - 18

3.1.1 Explain the duties and responsibilities responsibilities of computer personn personnel el 3.1.2 Explain methods of data processing (manual, mechanical and electronic) 3.1.3 Describe the different types of computers (Micro, Mini, Mainframe/Super, Digital, Analog, hybrid etc) 3.1.4 Describe the difference 3.2 Hardware

Pages 19 – 23

3.2.1 Main components of a computer system 3.2.2 Data flows between components of a computer. 3.2.3 Execution of a program and the involvement of the main components in this. 3.3 Peripherals, input, output and data storage

Pages 24 - 36

3.3.1 Principles of Operation 3.3.2 Performance characteristics 3.3.3 Types of situations in which they are useful, e.g. graphic devices. 3.4 Software components of computer systems.

Pages 37 - 61

3.4.1 The operating system and its functions. Describe the main features of an operating system. 3.4.2 Windows 95, 98, 2000----create directory, move around the move directories, and describe booting system, copy files from directory to another, files, back up files, rename files, undelete files e.t.c. 3.4.3 Application software and programming languages 3.4.4 The need of utility programs 3.4.5 Memory, devices and the Computer Processing Unit (C.P.U)

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3.4.6 File management systems 3.5 Main memory

Pages 62 - 65

3.5.1 Its use including its place in the memory hierarchy 3.5.2 Concepts of random and sequential access 3.5.3 access/cycle times 3.6 Arithmetic logic Unit (ALU)

Pages 66 – 67

3.6.1 Nature of ALU and flow of data between the functional units in it. 3.6.2 Relationship Relationship of ALU and other parts of the C.P.U. 3.7 Computer room environment and security

Pages 68 - 73

3.7.1 Requirements of the computer room 3.7.2 Security of hardware, software and information 3.8 Data processing

Pages 74 - 79

3.8.1 Data processing cycle 3.8.2 Data origination 3.8.3 Data verification 3.8.4 Data validation 3.9 Software delivery

Pages 80 - 87

3.9.1 Choosing software 3.9.2 Types of software 3.9.3 Advantages/disadvantages of integrated software off the shelf in-house contracted tailor made 3.10 Communication system basics  

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Pages 88 - 97

3.10.1 LAN networks

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3.10.2 WAN networks 3.11 Ethical challenges of computing      

Pages 98 - 104

information circulation software controls processing controls

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computer crime health issues 3.12 Applications (word processing)  

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load a program from hard disk create a new document enter text insert text delete text/move/replace text mail merge/ change line spacing underline/change underline/c hange margins/centre margins/centre obtain different fonts embolden/justify embolden/ justify margins

3.13 Spreadsheet                    

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Pages 125 - 168

install program/load program creating a spreadsheet/cursor manipulation using the half facility entering labels, values, formulas apply/replicate formulae insert columns and rows, delete columns and rows save the spreadsheet(file) spreadsheet(file) manipulate function key print spreadsheet or specified window retrieve spreadsheet

3.14 Database - Ms Access  

Pages 105 - 124

Pages 169 - 217

load program set up files containing alphabetic and numeric fields within the record enter data/add records/delete records/edit records sort records by a key field print selected fields search on more than one criteria, produce printouts

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4.0  General AIM 4.1To provide an understanding of the operation of the hardware of a computer system and the roles played by the unit of the system. 4.2To provide an understanding of the software of a computing system and its interaction with hardware. 4.3To introduce the students t of basic computer care and maintenance.

5.0 

Objectives 5.1Identify and describe the operation of major hardware units of a computer system. 5.2Describe the operation, characteristics characteristics and application of typical bulk storage devices. 5.3Identify and describe the duties and responsibilities of computer personnel. 5.4Describe the arithmetic and logic operations performed by the computer. 5.5Describe the architecture of different types of computers. 5.6State the requirements of a computer room environment and describe the security measures required for the computer room information.

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3.1 Functions of Computer Department in a company This IT department function  function  depends on the scale and business purposes of the company. The department is responsible for installations and maintenance of hardware and software requirements for the company. It’s It’s also  also tasked with training of users to ensure effective use of IT resources. This department should also develop the IT policy for the company to guide users. users.   3.1.1 Duties and responsibility of computer personnel 1. Computer Operator:  Operator:  Computer operators oversee the operation of computer hardware systems, ensuring that these machines are used as efficiently as possible. They may work with mainframes, minicomputers, or networks of personal computers. Computer operators must anticipate problems and take preventive action, as well as solve problems that occur during operations. The duties of computer operators vary with the size of the installation, the type of equipment used, and the policies of the employer. Generally, operators control the console of either a mainframe digital computer or a group of minicomputers. Working from operating instructions prepared by programmers, users, or operations managers, computer operators set controls on the computer and on peripheral devices required to run a particular job. Computer operators load equipment with tapes, disks, and paper, as needed. While the computer is running— running—which may be 24 hours a day for large computers— computers—computer operators monitor the control console and respond to operating and computer messages. Messages indicate the individual specifications of each job being run. If an error message occurs, operators must locate and solve the problem or terminate the program. Operators also maintain logbooks or operating records, listing each job that is run and events, such as machine malfunctions, malfunctions, that occur during their shift. In addition, computer operators may help programmers and systems analysts test and debug new programs. As the trend toward networking computers accelerates, a growing number of computer operators are working on personal computers (PCs) and minicomputers. In many offices, factories, and other work settings, PCs and minicomputers are connected in networks, often referred to as local area networks (LANs) or multi-user systems. Whereas users in the area operate some of these computers, many require the services of full-time operators. The tasks performed on PCs and minicomputers are very similar to those performed on large computers. As organizations continue to look for opportunities to increase productivity, automation is expanding into additional areas of computer operations. Sophisticated software, coupled with robotics, enables a computer to perform many routine tasks formerly done by computer operators. Scheduling, loading and downloading programs, mounting tapes, rerouting messages, and running periodic reports can be done without the

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intervention of an operator. Consequently, these improvements will change what computer operators do in the future. As technology advances, the responsibilities of many computer operators are shifting to areas such as network operations, user support, and database maintenance. maintenance. 2. Hardware/Software Technician: Provide technical support to end-users within the organization. Create, initiate and develop desktop computing environmentt in an organization. Install software programs and applications. environmen Determine, identify and troubleshoot technical problems relating to software and hardware. Install and configure software programs and applications. Execute tests and debug programs. Maintain and manage workstations, servers, printers and scanners and other related equipment. Ensure quality hardware and software support for end-users. Interconnectt workstations, terminals and existing data networks. Interconnec 3. Computer Programmers: Computer programmers write, test, and maintain the detailed instructions, called programs that computers must follow to perform their functions. They also conceive, design, and test logical structures for solving problems by computer. Many technical innovations in programming— programming—advanced computing technologies and sophisticated new languages and programming tools— tools— have redefined the role of a programmer and elevated much of the programming work done today. Job titles and descriptions may vary, depending on the organization. In this occupational statement, computer programmer   refers to individuals whose main job function is programming; this group has a wide range of responsibilities and educational e ducational backgrounds. 4. Database Administrator: A Database Administrator, Database Analyst or Database Developer is the person responsible for managing the information within an organization. As most companies continue to experience inevitable growth of their databases, these positions are probably the most solid within the IT industry. In most cases, it is not an area that is targeted for layoffs or downsizing. On the downside, however, most database departments are often understaffed, requiring administrators to perform a multitude of tasks. Depending on the company and the department, this role can either be highly specialized or incredibly diverse. The primary role of the Database Administrator to administer, develop, maintain and implement the policies and procedures necessary to ensure the security and integrity of the corporate database. Sub roles within the Database Administrator classification may include security, architecture, warehousing and/or business business analysis. Other primary roles will iinclude: nclude:

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Implementation of data models Implementation Database design Database accessibility Performance issues Capacity issues Data replication Table Maintenance

Database Administrators are often on-call and required to work as needed. This position carries an enormous amount of responsibility  responsibility  5. Systems Administrator: A system administrator's responsibilities might include:  

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Analyzing system logs and identifying potential issues with computer systems. Introducing and integrating new technologies into existing data center environments. Performing Performin g routine audits of systems and software. Performing backups. Performing  backups.   Applying operating Applying  operating system updates, patches, and configuration changes. Installing and configuring new hardware new hardware and software. and software.   Adding, removing, or updating user account information, resetting passwords, etc. passwords,  etc. Answering technical queries. Responsibility Responsib ility for security. for security.   Responsibility Responsib ility for documenting for documenting the configuration of the system. Troubleshooting any reported problems. System performance System  performance tuning.  tuning.  Ensuring that the network infrastructure is up and running.

6. Software Engineer: If Engineer: If you are considering considering a job as Software Engineer here is a list of the most standard responsibilities and duties for the Software Engineer position.  

Design, develop and manage software projects for clients. Analyze and evaluate user needs and develop software solutions. Write supporting documents for projects developed and tested. Develop Microsoft .net based web applications. Develop MS SQL server applications like views, triggers and stored procedures. Design and develop web user interfaces with back-end databases and other tools.

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Recommend technical feasibilities and solutions. Evaluate new technologies in the light of emerging trends and ttechnologi echnologies. es. Modify and update existing technologies improvise performances. performances. Troubleshoot and resolve difficult problems relating to software applications and programs.

7. Systems Analyst: Works out what tasks can be done by computer systems, designs the software and decides what hardware is required. When the system has been created, the systems analyst checks to see if the system can be improved. The responsibilities of a systems analyst are many and varied. More importantly a systems analyst is a key work at a company and thus what they do is critical for the overall welfare of a company. The systems analyst is charged with looking after the operating system and associated subsystems. In today's ever-increasing reliant computer age, this description makes them more critical than ever. The systems analyst must order provide support to the operating systems and hardware tools and generally has to make sure that things run and work as they should. If they can find out how to make things run more cheaply that is also good. The systems analyst needs to be on top of the industry. They have to be aware of all the available technology and the pros and cons of each. Keeping tabs of new technology is also critical as new technology is arriving all the time. They must know what technology provides the best cost effective performance. The systems analyst must provide and maintain a working environment which functions like it should. The systems analyst is doing his job if there are no fires to be put out. If no one wants him to solve a problem or troubleshoot something then everything is working as it should. 8. Computer Scientist: A computer scientist typically designs and develops complex hardware and software systems, along with software solutions. IT professionals professiona ls incorporate technological advances into existing systems and networks. 3.1.2 Methods of Data Processing Def Data processing:  processing:  operations (e.g., handling, merging, sorting, and computing) performed upon data in accordance with strictly defined procedures, such as recording and summarizing the financial transactions of a business. In automatic or electronic data processing the operations are performed by a computer.   In distributed data processing some or all of the operations are computer. performed in different locations at computer facilities connected by telecommunications telecommu nications links.

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Manual Data Processing: Manual data processing is the physical entering of data. This means a person is keying in the information. An example would be a doctor's office making you a chart, or a utility company establishing your new service. Once the data is manually entered, it does not have to be done again. Most of the time, your information can be retrieved by a phone number or social security number. You are now permanently entered in the system until it is deleted" "

Mechanical Processing: data processing operations are done using manual methods with the aid of mechanical tools such as the abacus. Electronic Data Processing: Computer data processing  processing   is any process that uses a computer program to enter data and summarise, analyse or otherwise convert data into usable  usable  information. The information. The process may be automated and run on a computer.   It involves recording, analysing, sorting, summarising, calculating, computer. disseminating and storing data. Because data is most useful when well-presented and actually informative informative,, data-processing systems are often referred to as information systems. Nevertheless, systems. Nevertheless, the terms are roughly synonymous, performing similar conversions; data-processing systems typically manipulate raw data into information, and likewise information systems typically take raw data as input to produce information as output. Data processing may or may not be distinguished from data conversion,  conversion,  when the process is merely to convert data convert data to another format, another format, and  and does not involve any data any data manipulation.  3.1.3 Types of Computers C omputers Five Generations of Modern Computers First Generation (1945-1956) With the onset of the Second World War,  War,  governments sought to develop computers to exploit their potential strategic importance. This increased funding for computer development projects hastened technical progress. By 1941 German engineer   Konrad Zuse had developed a computer, the Z3, to design airplanes and engineer missiles. The Allied forces, however, made greater strides in developing powerful computers. In 1943, the British completed a secret code-breaking computer called Colossus to decode German messages. The messages. The Colossus's impact on the development of the computer industry was rather limited for two important reasons. First, Colossus was not a general-purpose computer; it was only designed to decode secret messages. Second, the existence of the machine was kept secret until decades after the war. American efforts produced a broader achievement. Howard H. Aiken (1900-1973), a Harvard engineer working with IBM, succeeded in producing an all-electronic calculator by 1944. The purpose of the computer was to create ballistic charts for the U.S. the  U.S. Navy. It Navy. It was about half as long as a football field and contained about 500

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miles of wiring. The Harvard-IBM Automatic Sequence Controlled Calculator, or Mark I for short, was a electronic relay computer. It used electromagnetic signals to move mechanical parts. The machine was slow (taking 3-5 seconds per calculation) and inflexible (in that sequences of calculations could not change); but it could perform basic arithmetic as well as more complex equations. Another computer development spurred by the war was the Electronic Numerical Integrator and Computer (ENIAC), (ENIAC), produced by a partnership between the U.S. government and the University of Pennsylvania.  Pennsylvania.  Consisting of 18,000 vacuum tubes, 70,000 resistors and 5 million soldered joints, the computer was such a massive piece of machinery that it consumed 160 kilowatts of electrical power, enough energy to dim the lights in an entire section of Philadelphia. Developed Philadelphia. Developed by John Presper Eckert (1919-1995) (1919-1995)   and and  John W. Mauchly (1907-1980), ENIAC, unlike the Colossus and Mark I, was a general-purpose computer computer that computed at speeds 1,000 times faster than Mark I. In the mid-1940's John von Neumann (1903-1957) joined the University of Pennsylvania team, initiating concepts in computer design that remained central to computer engineering for the next 40 years. Von Neumann designed the Electronic Discrete Variable Automatic Computer (EDVAC) in (EDVAC) in 1945 with a memory to hold both a stored program as well as data. This "stored memory" technique as well as the "conditional control transfer," transfer," that allowed the computer to be stopped at any point and then resumed, allowed for greater versatility in computer programming. The key element to the von Neumann architecture was the central processing unit, which allowed all computer functions to be coordinated through a single source. In 1951, the UNIVAC I (Universal Automatic Computer), built by Remington Rand, became one of the first commercially available computers to take advantage of these advances. Both the U.S. the U.S. Census Bureau and General and General Electric owned UNIVACs. One of UNIVAC's impressive early achievements was predicting the winner of the 1952 presidential election, Dwight election, Dwight D. Eisenhower.  Eisenhower.  First generation computers were characterized by the fact that operating instructions were made-to-order made-to-order for the specific task for which the computer was to be used. Each computer had a different binary-coded program called a machine language that told it how to operate. This made the computer difficult to program and limited its versatility and speed. Other distinctive features of first generation computers were the use of vacuum tubes (responsible for their breathtaking size) and magnetic drums for data storage. Second Generation Computers (1956-1963) ( 1956-1963) By 1948, the invention of the transistor greatly changed the computer's development. The transistor replaced the large, cumbersome vacuum tube in televisions, radios and computers. As a result, the size of electronic machinery has been shrinking ever since. The transistor was at work in the computer by 1956. Coupled with early advances in magnetic-core memory, transistors led to second

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generation computers that were smaller, faster, more reliable and more energyefficient than their predecessors. The first large-scale machines to take advantage of this transistor technology were early supercomputers, Stretch by IBM and LARC by Sperry-Rand. These computers, both developed for atomic energy laboratories, could handle an enormous amount of data, a capability much in demand by atomic scientists. The machines were costly, however, and tended to be too powerful for the business sector's computing needs, thereby limiting their attractiveness. Only two LARCs were ever installed: one in the Lawrence Radiation Labs in Livermore, California, for which the computer was named (Livermore Atomic Research Computer) and the other at the U.S. Navy Research and Development Center in Washington, D.C.  D.C.  Second generation computers replaced machine language with assembly language, allowing abbreviated programming codes to replace long, difficult binary codes. Throughout the early 1960's, there were a number of commercially successful second generation computers used in business, universities, and government from companies such as Burroughs, Control Data,  Data,  Honeywell, Honeywell,   IBM, Sperry-Rand, and others. These second generation computers were also of solid state design, and contained transistors in place of vacuum tubes. They also contained all the components we associate with the modern day computer: printers, tape storage, disk storage, memory, operating systems, and stored programs. One important example was the IBM 1401, which was universally accepted throughout industry, and is considered by many to be the Model T of the computer industry. industry.   By 1965, most large business routinely processed financial information using second generation computers. It was the stored program and programming language that gave computers the flexibility to finally be cost effective and productive for business use. The stored program concept meant that instructions to run a computer for a specific function (known as a program) were held inside the computer's memory, and could quickly be replaced by a different set of instructions for a different function. A computer could print customer invoices and minutes later design products or calculate paychecks. More sophisticated high-level languages such as COBOL (Common Business-Oriented Language) and FORTRAN (Formula Translator) came into common use during this time, and have expanded to the current day. These languages replaced cryptic binary machine code with words, sentences, and mathematical formulas, making it much easier to program a computer. New types of careers (programmer, analyst, and computer systems expert) and the entire software industry began with second generation computers. Third Generation Computers (1964-1971) Though transistors were clearly an improvement over the vacuum tube, they still generated a great deal of heat, which damaged the computer's sensitive internal parts. The quartz rock eliminated this problem.  problem.   Jack Kilby, an engineer with Texas Instruments, developed Instruments,  developed the integrated circuit (IC) in 1958. The IC combined three

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electronic components onto a small silicon disc, which was made from quartz. Scientists later managed to fit even more components on a single chip, called a semiconductor. As a result, computers became ever smaller as more components were squeezed onto the chip. Another third-generation development included the use of an operating system that allowed machines to run many different programs at once with a central program that monitored and coordinated the computer's memory. Fourth Generation (1971-Present) After the integrated circuits, the only place to go was down - in size, that is. Large scale integration (LSI) could fit hundreds of components onto one chip. By the 1980's, very large scale integration (VLSI) squeezed hundreds of thousands of components onto a chip. Ultra-large scale integration (ULSI) increased that number into the millions. The ability to fit so much onto an area about half the size of a U.S. dime helped diminish the size and price of computers. It also increased their power, efficiency and reliability. The Intel 4004 chip, developed in 1971, took the integrated circuit one step further by locating all the components of a computer (central processing unit, memory, and input and output controls) on a minuscule chip. Whereas previously the integrated circuit had had to be manufactured to fit a special purpose, now one microprocessor could be manufactured and then programmed to meet any number of demands. Soon everyday household items such as microwave ovens,  ovens,  television sets and automobiles with electronic fuel injection incorporated microprocessors. microprocessors. Such condensed power allowed everyday people to harness a computer's power. They were no longer developed exclusively for large business or government contracts. By the mid-1970's, computer manufacturers sought to bring computers to general consumers. These minicomputers came complete with user-friendly software packages that offered even non-technical users an array of applications, most popularly word processing and spreadsheet programs. Pioneers in this field were Commodore,  Commodore,   Radio Shack and Apple Computers. In Computers. In the early 1980's, arcade video games such as Pac Man and home video game systems such as the Atari 2600 ignited consumer interest for more sophisticated, programmable home computers. In 1981, IBM introduced its personal computer (PC) for use in the home, office and schools. The 1980's saw an expansion in computer use in all three arenas as clones of the IBM PC made the personal computer even more affordable. The number of personal computers in use more than doubled from 2 million in 1981 to 5.5 million in 1982. Ten years later, 65 million PCs were being used. Computers continued their trend toward a smaller size, working their way down from desktop to laptop computers (which could fit inside a briefcase) to palmtop (able to fit inside a breast pocket). In direct competition with IBM's PC was Apple's Macintosh line, introduced in 1984. Notable for its user-friendly design, the Macintosh offered an operating system that allowed users to move screen icons instead of typing instructions.

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Users controlled the screen cursor using a mouse, a device that mimicked the movement of one's hand on the computer screen. As computers became more widespread in the workplace, new ways to harness their potential developed. As smaller computers became more powerful, they could be linked together, or networked, to share memory space, software, information and communicate with each other. As opposed to a mainframe computer, which was one powerful computer that shared time with many terminals for many applications, networked computers allowed individual computers to form electronic co-ops. Using either direct wiring, called a Local Area Network (LAN), (LAN), or  or telephone lines, these networks could reach enormous proportions. A global web of computer circuitry, the Internet, the Internet, for  for example, links computers worldwide into a single network of information. During the 1992 U.S. presidential election, vice-presidential candidate Al candidate  Al Gore promised to make the development of this so-called "information superhighway" an administrative priority. Though the possibilities envisioned by Gore and others for such a large network are often years (if not decades) away from realization, the most popular use today for computer networks such as the Internet is electronic mail, or E-mail, which allows users to type in a computer address and send messages through networked terminals across the office or across the world. Fifth Generation (Present and Beyond) Defining the fifth generation of computers is somewhat difficult because the field is in its infancy. The most famous example of a fifth generation computer is the fictional HAL9000 from Arthur C. Clarke's Clarke's novel, 2001: A Space Odyssey. Odyssey.  HAL performed all of the functions currently envisioned for real-life fifth generation computers. With artificial intelligence,  intelligence,  HAL could reason well enough to hold conversations with its human operators, use visual input, and learn from its own experiences. (Unfortunately, HAL was a little too human and had a psychotic breakdown, commandeering commandeering a spaceship and killing most humans on board.) Though the wayward HAL9000 may be far from the reach of real-life computer designers, many of its functions are not. Using recent engineering advances, computers may be able to accept spoken word instructions and imitate human reasoning. The ability to translate a foreign language is also a major goal of fifth generation computers. This feat seemed a simple objective at first, but appeared much more difficult when programmers realized that human understanding relies as much on context and meaning as it does on the simple translation of words. Many advances in the science of computer design and technology are coming together to enable the creation of fifth-generation computers. Two such engineering advances are parallel processing, which replaces von Neumann's single central processing unit design with a system harnessing the power of many CPUs to work as one. Another advance is superconductor technology, which allows the flow of electricity with little or no resistance, greatly improving the speed of information

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flow. Computers today have some attributes of fifth generation computers. For example, expert systems assist doctors in making diagnoses by applying the problem-solving problem-sol ving steps a doctor might use in assessing a patient's needs. It will take several more years of development before expert systems are in widespread use. Difference between computer generations Clock speed - newer processors generally run at higher speeds; this is a measure of how quickly the processor can operate, expressed in hertz. This is not the only relevant figure when comparing different processors. Number of cores - in the last couple of years, chip makers have touted the number of cores on their processors; think of each one as a separate minicomputer of sorts, able to complete its own tasks; a limitation with multicore processors is the software, which often cannot take full advantage of multiple cores.

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Types of Computers Classification Classificati on by Basic type  

a) Digital computers: these are computers used to process data b) Analog computers: these are designed to process data in a continuous wave like form. They process data from machines or instruments such as volt meter, thermometers and speedometers.  

c) Hybrid computers: are computers with a combination of digital and analog computer features.  

Classification Classificati on by Purpose a) General purpose: these are computers designed to carry out a variety of tasks.  

b) Special purpose: refers to a computer designed to carry out a single task such as weapon guiding and weather forecast.  

Classification Classificati on by Use a) Personal Computer: these are designed for use by an individual are sometimes portable. They can be connected to a network environment and are also called stand alone.  

b) Desktop: is generally a way of classifying whereby all computers used on a desk in an office environment are included.  

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c) Workstation: is a computer with more advanced features than an ordinary PC such as interconnection parts and graphical display units (e.g. used in banks).  

d) Lap top: this a very small computer which can be used comfortably on the lap. It is like a brief case in shape and has a flat screen.  

Classification Classificati on by capabilities capabilities (Processing and Storage) a) Main frame computer: is a general purpose computer with extensive storage capacity and processing capability. It can accommodate several users and is very expensive. It is used usually as a Host Computer on a Wide Area Network (WAN). It is usually situated at the headquarters of most organisations organisatio ns (banking system).  

b) Mini computer: refers to medium sized computers used for general purposes at a smaller scale but usually designed for special purposes. It can accommodate two to two hundred users and is usually off hand tasks of the main frame as front end processor. They can also control Local Area  

Networks (LANS) in branches of an organisation. c) Micro computer: these are the smallest computers used for small scale commercial applications. They are very cheap with limited storage capacity and processing capability in these computers several integrated circuits are replaced by a single circuit.  

NB: these boundary lines dividing the categories are not static due technological changes. Present computers are able to process faster than older main frames, this applies also to micro and mini computers. Exercise Questions  

1. Define the following terms i) Data ii) Information iii) Computer iv) Electronic Data processing v) Manual Data Processing [2marks each] 2. Identify duties of the following Data Processing personnel. i) Data processing Manager ii) Systems analyst iii) Computer Operator iv) Database administrator [5marks each]  

 

 

 

 

 

 

 

 

 

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3. List the main functions of a data processing department in an organisation. [10marks] 4. Explain any three (3) types of computers [12marks] 5. Explain any five factors that are likely to influence the data processing methods to be adopted by an organisation. [10marks]  

 

 

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3.2 HARDWARE 3.2.1 Main Components of a computer system A computer system is an electronic device that is used for data processing and made up of hardware and software components that work together to achieve this goal. Computer Hardware is the tangible or physical components of a computer system. Basic Components of a Computer system

Arithmetic Logic Unit (ALU)

Central Processing Unit CPU

Control Unit (CU) Output Input

Cache Memory

Output Devices

Input Devices

Main/Primary

Secondary Memory

The design complexity of CPUs increased as various technologies facilitated building smaller and more reliable electronic devices. The first such improvement came with the advent of the transistor.  transistor.   Transistorized CPUs during the 1950s and 1960s no longer had to be built out of bulky, unreliable, and fragile switching elements like vacuum tubes and electrical relays.  relays.  With this improvement more complex and reliable CPUs were built onto one or several printed circuit boards containing discrete (individual) components. During this period, a method of manufacturing many transistors in a compact space gained popularity. The integrated The integrated circuit (IC IC)) allowed a large number of transistors to be manufactured on a single semiconductor-based semiconductor- based die,  die,  or "chip." At first only very basic non-specialized digital circuits such as NOR gates were miniaturized into

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ICs. CPUs based upon these "building block" ICs are generally referred to as "smallscale integration" (SSI (SSI)) devices. SSI ICs, such as the ones used in the Apollo guidance computer,  computer,  usually contained transistor counts numbering in multiples of ten. To build an entire CPU out of SSI ICs required thousands of individual chips, but still consumed much less space and power than earlier discrete transistor designs. As microelectronic technology advanced, an increasing number of transistors were placed on ICs, thus decreasing the quantity of individual ICs needed for a complete CPU. MSI MSI   and LSI LSI   (medium- and large-scale integration) ICs increased transistor counts to hundreds, hundreds, and then thousands. In 1964 IBM introduced its System/360 its System/360 computer architecture which was used in a series of computers that could run the same programs with different speed and performance. This was significant at a time when most electronic computers were incompatible with one another, even those made by the same manufacturer. To facilitate this improvement, IBM utilized the concept of a microprogram (often called "microcode"), which still sees widespread usage in modern CPUs .[3]  The System/360 architecture architecture was so popular that it dominated the mainframe the mainframe computer market for decades and left a legacy that is still continued by similar modern computers like the IBM zSeries.  zSeries.  In the same year (1964), Digital Equipment Corporation (DEC) introduced another influential computer aimed at the scientific and research markets, the PDP-8. PDP-8. DEC  DEC would later introduce the extremely popular PDP-11 line that originally was built with SSI ICs but was eventually implemented with LSI components once these became practical. In stark contrast with its SSI and MSI predecessors, the first LSI implementation of the PDP-11 contained a CPU composed of only four LSI integrated circuits. circuits.[4]  Transistor-based computers had several distinct advantages over their predecessors. Aside from facilitating increased reliability and lower power consumption, transistors also allowed CPUs to operate at much higher speeds because of the short switching time of a transistor in comparison to a tube or relay. Thanks to both the increased reliability as well as the dramatically increased speed of the switching elements (which were almost exclusively transistors by this time), CPU clock rates in the tens of megahertz were obtained during this period. Additionally while discrete transistor and IC CPUs were in heavy usage, new highperformance performanc e designs like SIMD (Single Instruction Multiple Data)  Data)  vector processors began to appear. These early experimental designs later gave rise to the era of specialized supercomputers specialized  supercomputers like those made by Cray by Cray Inc.

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Microprocessors

Intel 80486DX2 microprocessor microprocessor in a ceramic PGA ceramic PGA package. The introduction of the microprocessor the microprocessor in the 1970s significantly affected the design and implementation of CPUs. Since the introduction of the first commercially available microprocessor (the Intel 4004) 4004) in 1970 and the first widely used microprocessor (the Intel 8080)  8080)  in 1974, this class of CPUs has almost completely overtaken all other central processing unit implementation methods. Mainframe and minicomputer manufacturers of the time launched proprietary IC development programs to upgrade their older computer architectures, and architectures, and eventually produced instruction set compatible microprocessors that were backward-compatible with their older hardware and software. Combined with the advent and eventual vast success of the now ubiquitous personal computer,  computer,  the term CPU   is now applied almost exclusively to microprocessors. Several CPUs can be combined in a single processing chip. Previous generations of CPUs were implemented as discrete components and numerous small integrated circuits (ICs) on one or more circuit boards. Microprocessors, on the other hand, are CPUs manufactured on a very small number of ICs; usually just one. The overall smaller CPU size as a result of being implemented on a single die means faster switching time because of physical factors like decreased gate parasitic capacitance.  capacitance.  This has allowed synchronous microprocessors to have clock rates ranging from tens of megahertz to several gigahertz. Additionally, as the ability to construct exceedingly small transistors on an IC has increased, the complexity and number of transistors in a single CPU has increased dramatically. This widely observed trend is described by Moore's law,  law,  which has proven to be a fairly accurate predictor of the growth of CPU (and other IC) complexity to date. While the complexity, size, construction, and general form of CPUs have changed drastically over the past sixty years, it is notable that the basic design and function has not changed much at all. Almost all common CPUs today can be very accurately described as von Neumann stored-program machines. As the aforementioned

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Moore's law continues to hold true, concerns have arisen about the limits of integrated circuit transistor technology. Extreme miniaturization of electronic gates is causing the effects of phenomena like  like  electromigration electromigration and subthreshold and subthreshold leakage to become much more significant. These newer concerns are among the many factors causing researchers to investigate new methods of computing such as the quantum computer,  computer,  as well as to expand the usage of parallelism and other methods that extend the usefulness of the classical von Neumann model. 3.2.2 Data flows between components of a computer The informations flows within a computer from the hard disk to the Southbridge chip(drive controller) on the motherboard then it goes to the Northbridge Chip (system memory controller) then it goes to the DRAM Chips (on the memory stick) then it goes to the CPU Chip Level 2 Cache Buffer SRAM then it goes to the CPU Chip Level 1 Primary Execution Cache Buffer SRAM Memory then it goes to the CPU Chip Execution Units for Processing and gets sent back to the Northbridge which either sends it back to the RAM to be stored for later use or through the AGP Slot (Accelerated Graphics Port) into the VRAM, then on to the GPU (graphics controller), then on to the RAMDAC which converts it to a signal which can be interpreted by your display. 3.2.3 Program execution and involvement of main components Typically, computer programs are stored in non-volatile memory until requested either directly or indirectly to be executed by the computer user. Upon such a request, the program is loaded into random access memory,  memory,  by a computer program called an operating system,  system,  where it can be accessed directly by the central processor. The central processor then executes ("runs") the program, instruction by instruction, until termination. A program in execution is called a process. Termination process.  Termination is either by normal self-termination or by error — software or hardware error.

Exercise 1. Define the following terms. i) Hardware ii) Processor iii) Arithmetic Logic Unit iv) Control Unit v) Integrated circuit 2. Explain the Fetch execute cycle  

 

 

 

 

 

 

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[10marks] [5marks]

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3.  State the components that constitute constitute the CPU. Outline briefly the role of each component in processing [10marks]  [10marks]  

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3.3 Peripherals (input and output) and data storage A peripheral peripheral is  is a device attached to a host computer but not part of it, and is more or less dependent on the host. It I t expands the host's capabilities, but does not form part of the core computer core computer architecture. Whether architecture. Whether something is a peripheral or part of a computer is not always clearly demarcated. A video capture card inside a computer case is not part of the core computer but is contained in the case. However, whether something can be considered a peripheral or not is a trivial matter of nomenclature, and is not a significant issue. Examples are computer printers,  printers,  image scanners,  scanners,  tape drives,  drives,  microphones,  microphones,   loudspeakers, webcams, loudspeakers,  webcams, and  and digital  digital cameras.  cameras.  Input Devices Computer peripherals peripherals are devices that are used to introduce data into the computer system are known as input devices. is any peripheral any  peripheral (piece of   computer hardware equipment) used to provide data and control signals to an information processing system (such as a computer).As computer ).As data is introduced to the computer system it is converted from analog to digital form, the form in the computer operates. Examples of Input Devices: 1. Keyboard:Keyboard:-   One of the main main input devices used on a computer, a PC's keyboard   looks very similar to the keyboards of electric typewriters, with some keyboard additional keys. Below is a graphic of the Saitek Gamers' keyboard with indicators pointing to each of the major portions of the keyboard.

Finally, today most users use the QWERTY style keyboards. Below is a graphic illustration of where each of the keys are on a U.S. QWERTY style keyboard.

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2.  2.  Mouse:- A hardware input device that allows the user to move the mouse pointer. Good examples of pointing devices are a computer mouse,  mouse,  trackball,  trackball,  lightpens,   touchpad and even the keyboard.  lightpens, keyboard.  To below is a picture of a Microsoft mouse and an example of a pointing device. 3. Barcode reader:-  reader:-  Lines of different widths and sizes representing data that, when read, will determine what the scanned object is. Bar codes are often used to help organize and be able to index information or prices about an object. Another example of how barcodes are used are the barcodes used by the US postal service that helps speed the delivery of mail. Below is an example of what a barcode for an address may look like.

Barcode readers and scanners A barcode reader or scanner also known as a point of sale (POS) scanner are hardware devices capable of reading a barcode and printing out the details of the product and/or logging that product into a database so a company can easily keep track of its inventory 4. Joystick:- An An   input device that looks similar to a control device you would find on an arcade game at your local arcades. A joystick A  joystick allows  allows an individual to easily move an object in a game such as navigating a plane in a flight simulator.  simulator.  The picture to the right is of the Logitech Freedom 2.4 joystick and an example of what a Joystick may look like.

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5. Scanner:- Hardware input device that allows a user to take an image and/or text and convert it into a digital file, allowing the computer to read and/or display the scanned object. A scanner scanner   is commonly connected to a computer USB,  USB,  Firewire, Parallel Firewire,  Parallel or SCSI or SCSI port. To the right is a picture and an example of a flatbed photo scanner, the Epson the Epson V300. Other types of scanners include: sheetfed scanner, scanner, which is a scanner that scans paper fed into it, handheld scanner, scanner, which is a scanner that is held and drag over a page to scan it, and a card scanner, scanner, which is a small scanner capable of scanning business cards.

6. Digital camera:- A type of camera that stores the  the  pictures or video or video it takes in electronic format instead of to film. There are several features that make digital cameras a cameras  a popular choice when compared to film cameras. First, the feature often enjoyed the most is the LCD the LCD display  display on the digital camera. This display allows users to view photos or video after the picture or video has been taken, which means if you take a picture and don't like the results, you can delete it; or if you do like the picture, you can easily show it to other people. Another nice feature with digital cameras is the ability to take dozens, sometimes hundreds of different pictures. To

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the right is a picture of the  the   Casio QV-R62, a 6.0 Mega Pixel digital camera used to help illustrate what a digital camera may look like. Digital cameras have quickly become the camera solution for most users today as the quality of picture they take has greatly improved and as the price has decreased. Many users however are hesitant in buying a digital camera because of the inability of getting their pictures developed. However, there are several solutions in getting your digital pictures developed. For example, there are numerous Internet companies capable of developing your pictures and send you your pictures in the mail. In addition, many of the places that develop your standard cameras film now have the ability to develop digital pictures if you bring them your camera, memory camera, memory stick, and/or pictures on CD. on CD.  

7.  7.  Microphone:- Sometimes abbreviated as mic, a microphone is a hardware peripheral originally invented by Emile Berliner in 1877 in  1877 that allows computer users to input audio into their computers. To the right is a visual example of a USB headset from Logitech from Logitech with a microphone. A popular solution for computer gaming.

8. Webcam:- A camera connected to a computer that allows anyone connected to the Internet the  Internet to view either a still pictures still pictures or motion video motion video of a user or other object. To the right is a picture of the Logitech the  Logitech QuickCam Express and an example of what a webcam may look like. Today, most webcams are either embedded into the

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display with laptop computers or connected to the USB or Firewire port on the computer.

9. OCR (optical character recognition):- usually abbreviated to OCR, is the mechanical or electronic translation of scanned  scanned  images of handwritten, typewritten or printed text into machine-encoded text. It is widely used to convert books and documents into electronic files, to computerize a record-keeping system in an office, or to publish the text on a website. OCR makes it possible to edit the text, search for a word or phrase, store it more compactly, compactly, display or print a copy free of scanning artifacts, and apply techniques such as machine translation, translation,   text-tospeech and text mining to it. OCR is a field of research in pattern recognition,  recognition,  artificial intelligence and computer and computer vision.  vision.  OCR systems require calibration to read a specific font; early font; early versions needed to be programmed with images of each character, and worked on one font at a time. "Intelligent" systems with a high degree of recognition accuracy for most fonts are now common. Some systems are capable of reproducing formatted output that closely approximates the original scanned page including images, columns and other non-textual components components.. 10. MICR (magnetic (magnetic ink character recognition):recognition):- is a character recognition technology used primarily by the banking industry to facilitate the processing of cheques.   The technology allows computers to read information (such as account cheques. numbers) off of printed documents. Unlike barcodes or similar technologies, however, MICR codes can be easily read by humans. MICR characters are printed in special typefaces with a magnetic ink or toner, usually containing iron oxide.  oxide.  As a machine decodes the MICR text, it first magnetizes the characters in the plane of the paper. Then the characters are passed over a MICR read head, a device similar to the playback head of a tape recorder.   As each character passes over the head it produces a unique waveform recorder. that can be easily identified by the system. The use of magnetic printing allows the characters to be read reliably even if they have been overprinted or obscured by other marks, such as cancellation stamps. The error rate for the magnetic scanning of a typical check is smaller than with optical character recognition systems. For well printed MICR documents, the "can't

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read" rate is usually less than 1% while the substitution rate (misread rate) is in the order of 1 per 100,000 characters. Output Devices An output device  device  is any piece of computer hardware equipment used to communicate the results of data processing carried out by an information processing system (such as a computer a computer)) to the outside world. In computing, input/output,  input/output,  or I/O, refers to the communication between an information processing system (such as a computer a computer), ), and the outside world. Inputs are the signals or data sent to the system, and outputs are the signals or data sent by the system to the outside. Examples of output devices: Speaker:   - Computers produce audio data that require output devices such as Speaker: speakers and headphones to deliver the sound to the user. Audio data is created by the computer and then sent to the audio card, which is located in an expansion slot. The card translates the data into audio signals, which are sent to the audio output device.   device. Headphones:   - are a pair of small loudspeakers,  Headphones: loudspeakers,  or less commonly a single speaker, with a way of holding them close to a user's ears and a means of connecting them to a signal source such as an audio amplifier, audio amplifier, radio  radio or CD or CD player.  player.  They are also known as stereophones stereophones,, headsets headsets or,  or, colloquially cans cans.. The in-ear versions are known as earphones earphones   or earbuds earbuds.. In the context of telecommunication,   the term headset is used to describe a combination of headphone and microphone used for two-way communication, communication,   for example with a telephone.   telephone. Screen (Monitor):(Monitor):- or  or  display display   (sometimes called a visual display unit) unit) is an electronic visual display for computers. The computers.  The monitor comprises the display device, circuitry, and circuitry,  and an enclosure. The display device in modern monitors is typically a a thin  thin film transistor liquid crystal display (TFT-LCD), while older monitors use a cathode ray tube (CRT).  (CRT).  Printer: Printer: Types of Printer A printer is an output device that produces text and graphics on paper. Major types of printer Printers can be divided into two main groups, impact printer  printer  and non-impact printer.. Impact printer produces text and images when tiny wire pins on print printer head strike the ink ribbon by by physically contacting contacting the paper. Non-impact printer printer produces text and graphics on paper without actually striking the paper. Printers can also be categorized based on the print method or print technology. The most popular ones are inkjet printer, printer, laser printer, printer, dot-matrix printer and printer and thermal printer. printer. Among these, these, only dot-matrix dot-matrix printer is impact impact printer and the others are non-impact printers.

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Some printers are named because they are designed for specific functions, such as photo printers, portable printers and all-in-one all-in-one /  / multifunction printers. Photo printers and portable printers usually use inkjet print method whereas multifunction printers may use inkjet or laser print method. Inkjet printers and laser printers are the most popular printer types for home and business use. Dot matrix printer was popular in 70’s and 80’s but has been be en gradually replaced by by inkjet printers fo forr home use. However, they they are still being used to print multi-part forms and carbon copies for some businesses. The use of thermal printersis limited to ATM, cash registers and point-of-sales terminals. Some label printers and portable printers also a lso use thermal printing. Due to the popularity of digital camera, laptop and SoHo office (small office / home office), the demand for photo printers, portable printers and multifunction printers has also increased substantially in recent years. Printer Technologies: Inkjet Printers Inkjet printers are non-impact printers which print text and images by spraying tiny droplets of liquid ink onto paper. paper. They are the most popular popular printers for home home use. Currently, most inkjet printers use either thermal inkjet or piezoelectric inkjet technology. Thermal inkjet printer uses uses heating elemen elementt to heat liquid ink to form vapor bubble, which forces the ink droplets onto the paper through the nozzle. Most inkjet manufacturers use this technology in consumer inkjet printers. Piezoelectric inkjet technology is used on all Epson printers and industrial inkjet printers. Instead of using heating heating element, these these printers use a piezoelectric piezoelectric crystal in each nozzle. nozzle. The piezoelectric crystal crystal changes shape shape and size based on the electric current received, and forces tiny droplets of ink onto the paper from the nozzle. Thermal inkjet printers use aqueous ink which is a mixture of water, glycol and dyes. These inks are inexpensive but they can only be used on paper or specially coated materials. materials. Piezoelectric inkjet printers allow allow the use of a wider range of inks, such as solvent inks, UV-curable inks, dye sublimation inks, and can print text and graphics on different uncoated materials. The inkjet head design is also divided into two main groups: fixed-head and disposable head. head. Fixed-head is built into into the printer and should should last for the the whole life of the printer. It produces more accurate output than cheap disposable head. The ink cartridges for fixed head printers are also cheaper as the print head does not need to be replaced. However, if the head is damaged, the entire printer has to be replaced.

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Disposable head head is included in replacement replacement ink cartridge. It is replaced each time time an ink cartridge runs runs out of ink. This increases the cost cost of ink cartridges cartridges and also limits the use of high high quality print head head in these cartridges. cartridges. However, a damaged damaged print head is not a problem as one can easily replace it with a new ink cartridge. Some printer manufacturers use disposable ink and disposable print head separately . The print head can last much longer than cheap disposable head and is separately. suitable for high volume volume printing. However, it can also be replaced replaced easily if the head is clogged or damaged. Although inkjet printers are generally used in home and small businesses, some manufacturers, manufactur ers, such as Hewlett Packard, have produced high end inkjet printers for industrial use. These professional professional inkjet printers are are usually used to print print advertising graphics or technical drawings. Advantages of inkjet printers:  printers:  1)

Low cost

2)

High quality of output, capable of printing fine and smooth details

3)

Capable of printing in vivid color, good for printing pictures

4)

Easy to use

5)

Reasonably fast

6)

Quieter than dot matrix printer

7)

No warm up time

Disadvantages of inkjet printers: 1)

Print head is less durable, prone to clogging and damage

2)

Expensive replacement ink cartridges

3)

Not good for high volume printing

4)

Printing speed is not as fast as laser printers

5)

Ink bleeding, ink carried sideways causing blurred effects on some papers

6)

Aqueous ink is sensitive to water, even a small drop of water can cause blurring

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7)

Cannot use highlighter marker on inkjet printouts

Many consumer inkjet printers are selling at very low price (under $100) these days. It is the printer manufacturer’s marketing strategy to reduce the price of the printers but dramatically dramatically mark up the price of replacement replacement cartridges. However, consumers still have the options to buy cheap compatible and remanufactured inkjet cartridges or ink refill kits to cut down printing cost.

Laser printers Laser Printers Laser printers are non-impact printers which can print text and images in high speed and high quality resolution, ranging from 600 to 1200 dpi. Unlike inkjet printers, laser printer use toner (black or colored powder) instead of liquid inks. A laser printer consists consists of these major componen components: ts: drum cartridge, cartridge, rotating mirror, mirror, toner cartridge cartridge and roller. The drum cartridge cartridge rotates as the paper paper is fed through. The mirror deflects laser beam across the surface of the drum. Laser beam creates charge that causes the toner to stick to the drum. As the drum rotates and presses on paper, toner is transferred from the drum to paper, creating images. Rollers then then use heat heat and pressure to fuse toner to paper. Colored laser laser printers add colored toner in three additional passes. Advantages of laser printers:  printers:  1)

High resolution

2)

High print speed

3)

No smearing

4)

Low cost per page (compared to inkjet printers)

5)

Printout is not sensitive to water

6)

Good for high volume printing

Disadvantages of laser printers:  printers:  1)

More expensive than inkjet printers

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2)

Except for high end machines, laser printers are less capable of printing vivid colors and high quality images such as photos.

3)

The cost of toner replacement and drum replacement replacement is high

4)

Bulkier than inkjet printers

5)

Warm up time needed

Dot-matrix printer Dot-matrix printer is an impact printer that produces text and graphics when tiny wire pins on the print print head strike the ink ink ribbon. The print head runs runs back and forth on the paper like a typewriter. When the ink ribbon pres presses ses on the paper, it creates dots that form text and images. Higher number of pins means that the printer prints more dots per character, thus resulting in higher print quality. Dot-matrix printers were very popular and the most common type of printer for personal computer in 70’s to 80’s.  80’s.  However, their use was gradually gradually replaced by inkjet printers in 90’s.  90’s.  As of today, dot matrix printers are only used in some pointof-sales terminals, or businesses where printing of carbon copy multi-part forms or data logging are needed. Advantages of dot matrix printer:  printer:  1)

Can print on multi-part forms or carbon copies

2)

Low printing cost per page

3)

Can be used on continuous form paper, useful for data logging

4)

Reliable, durable

Disadvantages of dot matrix printer:  printer:  1)

Noisy

2)

Limited print quality

3)

Low printing speed

4)

Limited color printing

Thermal printers

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Thermal printers use two types of printing technologies: direct thermal  thermal  and thermal transfer printing. transfer printing. Traditional thermal printers use direct thermal method by pushing electrically heated pins against against heat-sensitive paper paper (thermal paper). paper). The coating on the thermal paper turns black in the areas where it is heated, producing characters or images. Direct thermal thermal printers have no ink, ink, toner or ribbon. These printers printers are durable, easy to use use and cost less to print print than other printers. printers. However, the thermal paper is sensitive to heat, light, water, and abrasion and the text and images may fade over time. In thermal transfer printing, a thermal print head applies heat to a heat-sensitive ribbon, which melts ink onto paper and a wide range of materials to form text and images. The printouts can be extremely durable and can be stored over long period of time. Thermal printers are often used in cash registers, ATM and point-of-sales terminals. Direct thermal printing was used in some older fax machines before the 21st century. However, these old old models are now replaced replaced by new machines which which use laser and inkjet printing. Thermal printing iis s still considered as the best technology for bar code printing because it produces accurate, high quality images with exact bar widths. widths. Some portable portable printers and most label printers printers still use thermal printing method. Thermal printer is not the same as thermal inkjet printer. The latter uses inkjet print technology by heating liquid ink to form vapor bubble, which forces the ink droplet onto the paper from the nozzle. Specialty Printers Photo printer are color printers that produce photo lab quality pictures on photo Photo printers paper. They can also also be used to print documents. documents. These printers printers have a very high number of nozzles and can print very fine droplets for improved image quality. Some photo printers also have media card readers. They can print 4‖ x 6‖ photos directly from the media card of digital cameras without a computer in between. Theoretically, most inkjet printers and high end laser printers are capable of printing high quality pictures. Sometimes, these printers are marketed as ―photo printers‖.   However, a dedicated printers‖. dedicated photo printer is designed to print photos photos effectively and economically. economically. Apart from a higher number number of nozzles and very fine fine droplets, these printers also use additional cartridges, such as photo cyan, light magenta and

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light black. These additional color color cartridges allow the pri printing nting of more vivid and realistic photos and the result is better than ordinary inkjet and laser printers. MultiFunction / All-in-One Printers  Printers  Multifunction printer (MFP) is also known as all-in-one printer or multifunction device (MFD). It is a machine that includ includes es several functionalities functionalities including printer, printer, scanner, copier and fax. Multifunction printer printer is very popular in SoHo (small (small office / home office) office) offices. offices. It can use either inkjet or laser print method. Some multifunction printers also have media card readers, allowing printing of pictures directly from digital cameras without using a computer. Advantages of multifunction printers:  printers:  1)

2)

Low cost –  it is often cheaper to buy a multifunction printer than individual components (fax machine, scanner, printer, copier) separately Take up less room

Disadvantages of multifunction printers:  printers:  1)

If one component is broken, the entire machine has to be replaced

2)

Failure in any component will affect other functions

3) The print quality and speed may be lower than some stand alone components   components

Plotter:-Plotters create a hard copy rendition of a digitally rendered design. The Plotter:-Plotters design is sent to the plotter via a graphics card, and creates the design using a pen. Generally used with engineering applications, plotters basically draw an image using a series of straight lines.

Exercise 1. Indicate whether the following is an input/output device and describe how it operates or is used.  

i)

 

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ii) iii) iv) v)  

   

 

scanner web-cam speaker monitor

2. Describe the following types of printers i) Dot matrix ii) Thermal iii) Inkjet iv) laser  

 

 

 

 

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3.4 Software Components of computers system Computer software  software  (or simply software software)) refers to one or more computer programs and data held in the storage of a computer for some purpose.  purpose.  Program software performs the function of the program it implements, either by directly providing instructions to the computer hardware or by serving as  as  input to another piece of software. Data software.  Data software solely for its eventual useW. by Tukey other other program  program software software. . The term software was software  was exists first used in this sense by John by John in in 1957;  1957;   colloquially, the term is often used to mean application software. software.   In computer science and software and software engineering,  engineering, computer software is software is all information all information processed by computer by  computer system, programs system, programs and data. and data.   Computer software is so called in contrast to computer hardware, hardware,   which is the physical substrate which stores and executes (or "runs") the software. 3.4.1 

Operating System and its Functions

What is an Operating System? The operating system is the core software component of your computer. It performs many functions and is, in very basic terms, an interface between your computer and the outside world. In the section about hardware, a computer is described as consisting of several component parts including your monitor, keyboard, mouse, and other parts. The operating system provides an interface to these parts using what is referred to as "drivers". This is why sometimes when you install a new printer or other piece of hardware, your system will ask you to install more software called a driver. What does a driver do? A driver is a specially written program which understands the operation of the device it interfaces to, such as a printer, video card, sound card or CD ROM drive. It translates commands from the operating system or user into commands understood by the component computer part it interfaces with. It also translates responses from the component computer part back to responses that can be understood by the operating system, application program, or user. The below diagram gives a graphical depiction of the interfaces between the operating system and the computer component.  component. 

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Other Operating System Functions The operating system provides for several other functions including:  

     

 

System tools (programs) used to monitor computer performance, debug problems, or maintain parts of the system. Computer memory management. Processor time scheduling. scheduling. A set of libraries or functions which programs may use to perform specific tasks especially relating to interfacing with computer system components. Provide user interface to launch programs they want to work with.

The operating system makes these interfacing functions along with its other functions operate smoothly and these functions are mostly transparent to the user. Operating System Concerns As mentioned previously, an operating system is a computer program. Operating systems writteninby programmers whomay make mistakes. Therefore there canare be errors thehuman code even though there be some testing before the product is released. Some companies have better software quality control and testing than others so you may notice varying levels of quality from operating system to operating system. Errors in operating systems cause three main types of problems:  

System crashes and instabilities - These can happen due to a software bug typically in the operating system, although computer programs being run on the operating system can make the system more unstable or may even crash the system by themselves. This varies depending on the type of operating system. A system crash is the act of a system freezing and becoming unresponsive unresponsive which would cause the user to need to reboot.

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Security flaws Some software errors leaveAs a door thediscovered, system to be broken into- by unauthorized intruders. theseopen flawsfor are unauthorized intruders may try to use these to gain illegal access to your system. Patching these flaws often will help keep your computer system secure. How this is done will be explained later. Sometimes errors in the operating system will cause the computer not to work correctly with some peripheral devices such as printers.

Operating System Types There are many types of operating systems. The most common is the Microsoft suite of operating systems. They include from most recent to the oldest:

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Windows XP Professional Edition - A version used by many businesses on workstations. workstation s. It has the ability to become a member of a corporate domain. Windows XP Home Edition - A lower cost version of Windows XP which is for home use only and should not be used at a business. Windows 2000 - A better version of the Windows NT operating system which works well both at home and as a workstation at a business. It includes technologies which allow hardware to be automatically detected and other enhancements over Windows NT. Windows ME - A upgraded version from windows 98 but it has been historically plagued with programming errors which may be frustrating for home users. Windows 98 - This was produced in two main versions. The first Windows 98 version was plagued with programming errors but the Windows 98 Second Edition which came out later was much better with many errors resolved. Windows NT - A version of Windows made specifically for businesses offering better control over workstation capabilities to help network administrators. Windows 95 - The first version of Windows after the older Windows 3.x versions offering a better interface and better library functions for programs.

There are other worthwhile types of operating systems not made by Microsoft. The greatest problem with these operating systems lies in the fact that not as many application programs are written for them. However if you can get the type of application programs you are looking for, one of the systems listed below may be a good choice.  

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Unix - A system that has been around for many years and it is very stable. It is primary used to be a server rather than a workstation and should not be used by anyone who does not understand the system. It can be difficult to learn. Unix must normally run an a computer made by the same company that produces the software. Linux - Linux is similar to Unix in operation but it is free. It also should not be used by anyone who does not understand the system and can be difficult to learn. Apple MacIntosh - Most recent versions are based on Unix but it has a good graphical interface so it is both stable (does not crash often or have as many software problems as other systems may have) and easy to learn. One drawback to this system is that it can only be run on Apple produced hardware.

3.4.2 Using Windows 95, 98, 2000, XP Understanding File Organization Understanding file names and organization will make using your computer less stressful and more efficient. This knowledge will help in managing

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files files files files

on your local hard drive or a network drive, shared through e-mail attachments, shared through FTP (File Transfer Protocol), and put on the Web server for your Web site.

Files are organized by using folders (directories) on a physical location — just like paper documents within folders in file cabinet drawers. File Each letter, slide show, spreadsheet, or database you create is stored as a file. Every file saved has a filename filename.. You can use multiple words for the filename; for example, Letter to Sam. Sam. Do NOT use special characters, \ / : * ? " < > | . Every file also has a three-letter extension extension,, assigned by the Windows system, that associates it with a specific program. For example, a WordPerfect complete file name would be "Letter to Sam.wpd" and a Word file name would be "Letter to Sam.doc".

Folder You can store or organize similar types of files within a folder. You create as many folders and subfolders as you need. Folders organize the files in a logical manner, like using manila folders inside hanging folders to organize paper documents in a file cabinet drawer. A good place to put your folders and files is in the "My Documents" folder on your local hard drive — to provide easy backup. Disk drive The physical location where folders and files can be found. A disk drive name consists of a single letter and a colon. Drive A: = First floppy disk drive Drive C: = First hard disk drive Drive D - Z: = optional drives (2nd hard drive, CD-ROM or DVD drive, ZIP drive, and network drives) Path name The complete name of your file on a computer actually includes the  path  name. A  path name. path simply describes where a file is located on your computer or the network. The path name lists the drive (such as the hard disk, floppy disk, or CD-ROM) and folder that contains your data file. When you use the Recycle Bin or Find/Search feature, you will see the path name listed for each file.

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Complete path and file name examples: C:\My Documents\Letter to Sam.wpd A:\picture of john.jpg V:\7PKP\newsletter\Sept.rtf Viewing Folders and Files To start Windows Explorer, click on the Start button and select Programs. In Windows 98, next click on Windows Explorer to start the program. In Windows 2000 & XP, click on Accessories, then Windows Explorer. Or, you can use a shortcut to open the Windows Explorer program — right-click on the My Computer icon on your Desktop and choose Explore  from the Shortcut menu. Explore from NOTE for Windows XP users: To see the My Computer icon on the desktop, you may need to change the Start menu to the "Classic" view. Right-click on the Start button and select Properties  from the Shortcut menu. Select "Classic Start Menu" and click Properties from the OK button. The Explorer  window   window has two panes: the " Folders" pane, on the left, showing you all connected drives (under My Computer) and folders on one drive and the "Contents" pane, on the right, showing the contents of the selected drive or folder. To expand the view of a drive or folder in the "Folders" pane, click on the + symbol next to it and you will see more detail in the hierarchical view. To see the contents of a folder, click once on the name or folder icon. Depending on your version of Windows and changes you have made to the View option, you will see your files and folders shown in different ways. Figure 1 above shows the Windows Classic look with the "Details" View option. To get the Classic look,    

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in Windows 98, uncheck the as Web Page option on the View V iew menu. in Windows 2000, select Tools > Folder Options from the menu. Then select the Use Windows classic folders option in the "Web View" section (second set of options) in the General tab area. Next select the View tab and check (turnon) the option to Display the full path in the address bar. Windows XP requires no changes.

The preferred Contents pane view is the Details  option because you see the Name, Details option Size, Type (program association), and Modified (date and time) properties for each file and folder. To see the Details View : Choose View > Details from the menu bar. To make Windows use this view option as your default, you need to make one more change. Go to Tools > Folder Options and select the View tab in the dialog box. Then uncheck (turn off) the option to Remember each folder's view settings. settings.

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The default listing in the Details view is alphabetical by Name. The column headings are active buttons that you can click to sort the listing in different orders. Click on any column heading once to list in ascending order and again to list in descending order. TIP: In the Details view, Explorer can automatically adjust all the columns to fit to the width of the text. Click anywhere in the Contents pane, then hold down the key and press the Plus key on the numeric keypad. NOTE: The default setting of Windows Explorer is to NOT display the three-letter extension of the file name. You don't need to see the extension because in the Details view, the file "Type" column tells you the program associated associated with the file. If you want to see the the file extension name, go to Tools > Folder options. In the dialog box, select the View tab and select Hide file extensions for known file types  types  to turn it off (uncheck). Managing Files and Folders To create a new folder: 1. Select the location for the folder. For example, select the "My Documents" folder to create a subfolder within My Documents. Putting all your files in folders under My Documents will make it easier and quicker to make backups. Choose File > New > Folder from the menu bar. Or, right-click on a blank area of the Contents pane and choose New > Folder from the Shortcut menu. 2. Type in a folder name and press the key.  

 

You can move or copy files by using the Cut/Copy/Paste procedure you are used to using in your word processor. There are also other ways to move or copy files and you can find information on those options in the Help index.

TIP: There are two ways to select multiple files or folders. To select consecutive files or folders, click the t he first item, press and hold down the key, and then click the last item. To select files or folders that are not consecutive, click the first item, press and hold down the key, and then click each additional item.

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To move files or folders: 1. Select the file(s) or folder(s) to move. 2. Choose Edit > Cut (or click on the Cut button on the Toolbar or right-click on a file or a folder to move and choose Cut from the Shortcut menu). 3. Select the destination folder.  

 

 

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4. Choose Edit > Paste (or click on the Paste button on the Toolbar or right-click on the destination folder and choose Paste from the Shortcut menu).  

To copy files or folders: 1. Select the file(s) or folder(s) to copy.  

 

2. 3. 4.

 

 

Choose Copyto (or click on choose the Copy button the Toolbarmenu). or right-click on a file Edit or a>folder copy and Copy fromon the Shortcut Select the destination location (for example, a different disk drive). Choose Edit > Paste (or click on the Paste button on the Toolbar or right-click on the destination folder and choose Paste from the Shortcut menu).

TIP: If you are copying files or folders to a disk or CD to make a backup, you may want to check the total size of the files to make sure they will fit on the disk. After selecting the files or folders, right-click on any selected item and choose Properties from the Shortcut menu. In the Properties dialog box you will see the information on the number of files, number of folders, and total size of all selected items. Click OK. Copy your files if there is enough room on the disk. To rename a file or folder: 1. Select the file or folder to rename. 2. Choose File > Rename from the menu bar (or right-click on the file or folder name and choose Rename from the Shortcut menu). 3. Type the new file or folder name in the t he text box. 4. Press key.  

 

 

 

To find a file: If you don't remember where a file is located, you can use the Find   feature in Windows 98 and the Search Search feature  feature in Windows 2000/XP. Windows 98 1. Choose Tools > Find > Files or Folders from the menu bar. This will open a separate window. 2. Enter part of the file name in the "Named" text box. 3. If you want to search the entire hard drive, make sure the "Look in" box is showing (C:). 4. Click the Find Now button. for a partial listing of files and folders found using "doc" as the search criteria. The files/folders will be listed in alphabetical order within folders.)  

 

 

 

Windows 2000/XP

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1. Click on the Search Button on the Toolbar. The Search pane will replace the Folders pane. In Windows XP, select "All files and folders." o 2. Enter part of the file name in the "Search for files or folders named" or "All or part of the file name" text box. 3. If you want to search the entire hard drive, make sure the "Look in" box is showing (C:). 4. Click the Search Now button. for a partial listing of files and folders found using "doc" as the search criteria. The files/folders will be listed in alphabetical order within folders.)  

 

 

 

 

The search results list can be sorted by any column. Click on the column heading once to list in ascending order and again to list in descending order. To move a file from the old folder to a new folder, follow the instructions under "To move files or folders." To open a file to look at its contents, double-click on the file name. NOTE for Windows 2000/XP users: Use the Back button on the Toolbar to go to the previous list of files. You will need to click on the Folders button on the Toolbar to see your list of drives and folders again in the left pane. TIP: You can also find or search for a file by its content or search by a date range without a file name. See the Help information for details details.. To delete a file(s) or folder(s): 1. Select the file(s) or folder(s) to be deleted. 2. Press key (or right-click on the file or folder to be deleted and choose Delete from the Shortcut menu). 3. Click Yes Yes in  in the Confirm File Delete dialog box to put the file in the Recycle Bin.  

 

 

TIP: Deleting a folder also deletes all files in that folder. To restore deleted file(s) or folder(s) while in Windows Explorer: If you deleted the wrong file, select Edit > Undo from the menu bar. The Undo menu item will show the last function performed and if it isn't the "Delete" option, you need to select multiple Undo's to get to the Delete choice. This retrieves the file and places it in the original folder it was deleted from. NOTE: The Undo option only works for the current session in the Windows Explorer program. After you exit Windows Explorer, you will need to use the Recycle Bin to restore deleted files or folders. Please see the next section. Using the Recycle Bin

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The Recycle Bin acts Bin acts as a temporary storage area for files deleted from your local hard drive. The Recycle Bin does NOT keep a copy of any file or folder deleted from other locations (diskette, ZIP drive, or network drive). Deleting a file or folder to the Recycle Bin does not permanently delete the file from your local hard drive. The Recycle Bin allows you to restore deleted files. To permanently delete the file and regain some hard drive space, you need to delete the file(s) from the Recycle Bin. To restore deleted file(s) from the Recycle Bin: 1. Open the Recycle Bin outside of Windows Explorer by double-clicking on its icon on the Desktop. 2. Select the file(s) to be restored. 3. Choose File > Restore from the menu bar (or right-click on the file or folder to be restored and choose Restore from the Shortcut menu).  

 

 

To delete a file(s) from the Recycle Bin:  

1. Select the Recycle Bin icon inside Windows Explorer or open the Recycle Bin on your desktop. 2. Select the file(s) to be deleted. NOTE: The column headings in the Recycle Bin are active buttons, so you can sort the files to list the way it is easiest for you to work with them. 3. Press key (or right-click on the file or folder to be deleted and choose Delete from the Shortcut menu). 4. Click Yes Yes in  in the Confirm File Delete dialog Delete dialog box.  

 

 

To delete all files at one time from the Recycle Bin, use the Empty Recycle Bin  Bin  option: 1. Choose File > Empty Recycle Bin.  

 

2. Click Yes Yes in  in the Confirm Multiple File Delete dialog Delete dialog box.

Creating and Using Shortcuts To create a desktop shortcut to Windows Explorer: You can quickly create a desktop shortcut or QuickLaunch shortcut to this program or other programs. The default QuickLaunch toolbar is a section of 3 or 4 icons on the Taskbar next to the Start button. You only need to click once on these icons to open the program.

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1. Click on the Start button and select Programs. 2. Find your program name. Right-click and hold and drag to the desktop or QuickLaunch area and release. (When you drag the program name to the QuickLaunch area you will see an I-beam that allows you to place the icon in the sequence you want.) 3. In Windows 98/2000, choose Create Shortcut(s) Here  Here  from the Shortcut menu. In Windows XP, choose Copy Here from Here from the Shortcut menu.  

 

 

NOTE for Windows XP users: If you don't see the QuickLaunch icons on the Taskbar, right-click on the Taskbar and select Toolbars > QuickLaunch from the Shortcut menu. To create a desktop shortcut for a frequently used file: 1. In Windows Explorer, right-click and hold on the file name. 2. Drag it to the desktop and release. NOTE: Windows Explorer needs to be running in a smaller window, not maximized, so you can see the desktop. 3. Select the Create Shortcut(s) Here option. Here option.  

 

 

When you double-click on the shortcut icon you will open the program and the file at the same time. Keyboard shortcuts These keyboard shortcuts simplify various operations and give your hand a rest from using the mouse. Here's a list of selected shortcuts and their effects. Windows key = Display Start Menu (and taskbar, if it isn't visible) Use the arrow keys to move up and down the menu and to move to the right (open sub-menus). Use the Enter key to make a selection. Windows key + E = Start Windows Explorer Windows key + F = Find/Search F ind/Search files or folders Ctrl + Windows key + F = Find a computer These shortcut keystrokes work in all Windows programs: Alt + F4 = Exit the program Esc = Cancel (in menus and dialog boxes) Ctrl+A = Select all Ctrl+C = Copy Ctrl+X = Cut Ctrl+V = Paste Ctrl+S = Save current document with same name Ctrl+Z = Undo

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If you want a list of additional keyboard shortcuts, click on the Start button and then select Help. Use the Search  feature to look for keyboard shortcut . Search feature

3.4.3 Application software and programming programming languages Application Software Is the general designation of computer programs for performing user tasks. Application software may be general purpose (word processing,  processing,  web browsers, ...) or have a specific purpose (accounting, truck scheduling, ...). Application software contrasts with (2} system software,  software,  a generic term referring to the computer programs used to start and run computer systems and networks; and (3) programming tools, such tools, such as compilers and linkers, used to translate and combine computer program source code and libraries into executable programs (programs that will belong to one of the three said categories). Application software is a subclass of computer software that employs the capabilities of a computer directly and thoroughly to a task that the user wishes to perform. This should be contrasted with system software which is involved in integrating a computer's various capabilities, but typically does not directly apply them in the performance of tasks that benefit the user. In this context the term application refers to both the application software and its implementation. A simple, if imperfect analogy in the world of hardware would be the relationship of an electric light bulb (an application) to an electric power generation plant (a system). The power plant merely generates electricity, not itself of any real use until harnessed to an application like the electric light that performs a service that benefits the user. Typical examples of software applications are word processors, spreadsheets, and media players. Multiple applications bundled together as a package are sometimes referred to as an application suite. Some might bundle together a word processor, a spreadsheet, and several other discrete applications. The separate applications in a suite usually have a user interface that has some commonality making it easier for the user to learn and use each application. commonality And often they may have some capability to interact with each other in ways beneficial to the user. For example, a spreadsheet might be able to be embedded in a word processor document even though it had been created in the separate spreadsheet application. User-written software tailors systems to meet the user's specific needs. User-written software include spreadsheet templates, word processor macros, scientific simulations, graphics and animation scripts. Even email filters are a kind k ind of user software. Users create this software themselves and often overlook how important it is. In some types of embedded systems, the application software and the operating system software may be indistinguishable to the user, as in the case of software used to control a VCR, DVD player or Microwave M icrowave Oven.

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Programming Languages Programming A program is a set of instructions that tell the computer to do various things; sometimes the instruction it has to perform depends on what happened when it performed a previous instruction. This section gives an overview of the two main ways in which you can give these instructions, or ―commands‖ as they are usually called. One way uses an interpreter , the other a compiler . Evolution of Programm Programming ing Computer programming languages have evolved into four generations beginning with languages that were tied to the hardware and evolved into general purpose programming languages. First Generation The first generation of programming programming language were machine languages which were used by the first computers. This generation of programming languages were written in binary, a series of zeros and ones. Binary is difficult to read and errors occurred frequently. Machine languages were created differently for different for each CPU. Machine dependency was a problem because this programming language would only work for the system that it was written for. Second Generation When the second generation of programming languages were created, assembly languages did not completely resolve the issue of machine dependency. The assembly programming language was written in a more simplistic form, and at a higher level of abstraction machine language, instead of a series of zeros and ones there were symbols (percents, dollar and portions of a word and number combination used to make commands. Although assembly languages seem easier than the machine languages; machine dependency is still an existing problem. ThirdGeneration   ThirdGeneration Third generation programming languages were converted from English into machine language; compilers were used to convert these instructions. Languages such as C++ and Visual Basic are third generation programs that are well-known today. Important elements of assembly and machine language were not used for this generation of languages. Machine dependency was not a problem encountered by the generation of programming languages; but there was a need for a different type of processor to write each source code. Third generation programming languages are quite difficult to write, but people who are not technically inclined would find it easy to write programs in fourth generation programming language languages. s. Fourth Generation Fourth generation programming languages are strictly for applications that will process fourth generation commands. Object-oriented programming should be used

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when programming is focused on a specific concept, rather than a process. Java, C++, and Smalltalk are used for this purpose.

Compilation and Interpretation of Computer Programs Before a program can be executed on a computer, it must be translated to machine code. Alternatively it must be simulated by another program, called an interpreter. A compiler is a program that translates a programming language called the source programming language into another programming language called the destination language. Usually this source is a high level language while the destination language is machine code. An interpreter may require that the source programming language be compiled into an intermediate form before interpretation, called byte code. This is a more low level language for which it is easier to write an interpreter. 3.4.4 Utility programs Software utilities/Utility Software is a type of computer system software also referred to as service program, tool, service routine, or utility routine. Software Utilities are specifically designed to help the end-user manage and tune the computer hardware/Software, Operating system or application software and perform as single precise task as opposed to application software which performs multi-tasking. Utility software can be seen in many operating systems to day e.g. Windows XP, Windows Vista, Mac OS X etc. 3.4.5 Memory, devices and Computer Processing Unit (C.P.U)

Among the least understood aspects aspects of a computer’s operating system and function has to do with memory. Many people assume that their computer only has one sort and that it has limitless space available. When their computer begins to run

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sluggishly or not at all, many are surprised to t o learn that the trouble is the system’s memory and it's simple to fix. Before you are forced to learn the hard way about your computer’s memory, we've provided a brief outline of the different types of memory and their roles. Fast, powerful CPUs need quick and easy access to enormous quantities of data in order to maximize their performance. If the CPU can't get to the data it requires, it literally halts and waits for it. Modern CPUs running at speeds of about 1 gigahertz can run through massive quantities of data -- potentially billions of bytes per second. The problem that computer designers confront is that memory that can keep up with a 1-gigahertz CPU is exceedingly expensive -- much more expensive than anyone can afford in large quantities. Computer designers have solved the cost problem by "tiering" memory -- using expensive memory in small quantities and then backing it up with w ith larger quantities of less costly memory. There are different types of computer memory designated designated to store different types of data. They also have varied capabilities and specialties when it comes to storing essential information inside the computer. The best known computer memory is the RAM, also known as Random Access Memory. It's called random access because any stored data can be accessed directly if you know the precise row and column that intersect a certain memory cell. In this type of computer memory, memory, data can be accessed in any order. RAM’s exact opposite is called SAM or Serial Access Memory, which stores data in a series of memory cells that can only be accessed in order. It works very much like a cassette tape where you have to go through other memory cells before accessing the data that you're seeking. Secondary/Auxiliary Secondary/Auxil iary storage Also known as external memory and memory and auxiliary storage, storage, secondary storage is storage is a storage medium that holds information until it is deleted or overwritten regardless if the computer has power. For example, a floppy disk drive and hard disk drive are both good examples of secondary storage devices. As can be seen by the below picture there are three different types of storage on a computer, although primary storage is accessed much faster than secondary storage because of the price and size limitations secondary storage is used with today's computers to store all your programs and your personal data. The secondary memory is used to store the data permanently in the computer. The secondary storage devices are usually as follows: hard disk drives –  this is the most common type of storage device that is used in almost all the computer systems. The other ones include the floppy the floppy disk drives, the drives, the CD ROM, and ROM, and the DVD the DVD ROM. The ROM. The flash memory, the USB the USB data card etc. The storage devices are used to record the data over any storage surface. The memories may also be of different types depending upon the architecture and the design like the optical data storage memory, magnetic media storage and the mechanical storage media etc and also the flash memory devices etc.

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The storage devices are actually defined as the peripheral unit which holds the data like the tape, the tape, disk,  disk, or flash memory card etc. The most of the drives that are used for the purpose of data storage are fragile and the data can be easily corrupted in them. The data storage devices are the ones that are also used for the backup and the archiving of the data. The data storage devices were at a time in the past used to be too costly and expensive. But these days the data storage devices are becoming cheap day by day. Hence the data storage devices price is falling. So, we are in a position to get a storage device for a comparatively cheaper price than the earlier drive. The technology is improving a lot and now the memory storage capacity has gone up TB. The data in the storage devices can be in the form of the files, databases, digital video and the audio etc. The storage devices that are called as the non-volatile can store the data permanently until otherwise erased purposely. This is in the case of the hard disk drives or the floppy disk drives. The other kinds of the storage media like for example the CD and the DVD can even have again two types of the storage; the first one is that in which the data once written cannot be erased. It is stored permanently over it. While the second type of the CD’s or the DVD’s are called as the rewritable; where in the data that is once written can be erased completely and the same storage device can be used again for storing the different data. Secondary memory devices 1. Hard Drive A hard disk drive ( drive (hard a non-volatile storage device for hard disk , hard drive, drive, HDD) is a non-volatile digital data. It features one or more rotating rigid platters on a motor-driven spindle within a metal case. Data is encoded magnetically by read/write heads that float on a cushion of air above the platters. Hard disk manufacturers quote disk capacity in SI SI-standard -standard powers of 1000, wherein a terabyte is 1000 gigabytes and a gigabyte is 1000 megabytes. With file systems that measure capacity in powers of 1024, available space appears somewhat less somewhat  less than advertised capacity. The first HDD was invented by IBM in 1956. They have fallen in cost and physical size over the years while dramatically increasing capacity. Hard disk drives have been the dominant device for secondary storage of data in general purpose computers since the early 1960s. They have maintained this position because advances in their areal recording density have kept pace with the requirements for secondary storage. Form factors have also evolved over time from large standalone boxes to today's desktop systems mainly with standardized 3.5-inch form factor drives, and mobile and mobile systems mainly using 2.5-inch drives. Today's HDDs operate on high-speed serial interfaces, i.e., Serial i.e., Serial ATA (SATA) or Serial or Serial attached SCSI (SAS).

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2. Magnetic tape Magnetic tape is a medium for magnetic recording, made of a thin magnetizable coating on a long, narrow strip of plastic. It was developed in Germany, based on magnetic wire recording. Devices that record and play back audio and video using magnetic tape are tape recorders and video tape recorders. A device that stores computer data on magnetic tape is a tape drive (tape unit, streamer). Magnetic tape revolutionized broadcast and recording. When all radio was live, it allowed programming to be prerecorded. At a time when gramophone records were recorded in one take, it allowed recordings in multiple parts, which mixed and edited with tolerable loss in quality. It is a key technology in early computer development, allowing unparalleled amounts of data to be mechanically created, stored for long periods, and to be rapidly accessed. Today, other technologies can perform the functions of magnetic tape. In many cases these technologies are replacing tape. Despite this, innovation in the technology continues continues and tape is still widely used. Over years, magnetic tape can suffer from deterioration called sticky-shed syndrome. Caused by absorption of moisture into the binder of the tape, it can render the tape unusable.

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3. Magnetic disks

4. Floppy disks A floppy disk is disk is a data storage medium that is composed of a disk of thin, flexible ("floppy") magnetic storage medium encased in a square or rectangular plastic shell. Floppy disks are read and written by a floppy disk drive  drive  or FDD FDD,, [2]  Invented by the American information American information technology company company IBM,  IBM, floppy  floppy disks in 8 inch, 5¼ inch and 3½ inch forms enjoyed nearly three decades as a popular and ubiquitous form of data storage and exchange, from the mid-1970s mid- 1970s to the late 1990s. late 1990s.   While floppy disk drives still have some limited uses, especially with legacy industrial computer equipment, they have now been superseded by USB by  USB flash drives, drives, external  external hard disk drives, CDs, drives,  CDs, DVDs,  DVDs, Blu-Ray  Blu-Ray disc, disc, memory  memory cards and computer and computer networks.  networks. 

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5. CD ROM CD-ROM (pronounced  /ˌsiːˌdiːˈrɒm/, m/,   an acronym of "compact disc read-only memory")) is a pre-pressed compact disc that contains data accessible to, but not memory" writable by, a computer for data storage and music playback, the 1985  ―Yellow Book‖  standard developed by Sony by Sony and Philips and Philips adapted the format to hold any form of  binary  binary data.  data.  CD-ROMs are popularly used to distribute computer software,  software,  including games and multimedia applications, though any data can be stored (up to the capacity limit of a disc). Some CDs hold both computer data and audio with the latter capable of being played on a CD a CD player, while player, while data (such as software or digital video) is only usable on a computer (such as ISO 9660 format PC CD-ROMs). These are called enhanced CDs.  CDs.  Although many people use lowercase letters in this acronym, proper presentation is in all capital letters with a hyphen between CD and ROM. At the time of the technology's introduction it had more capacity than computer hard drives common at the time. The reverse is now true, with hard drives far exceeding CDs, CDs, DVDs  DVDs and Blu-ray, though Blu-ray,  though experimental descendants of it such as HVDs  HVDs may have more space and fastersome data rates than today's biggest hard drive.as CD-ROM discs are identical in appearance to audio CDs,  CDs,  and data are stored and retrieved in a very similar manner (only differing from audio CDs in the standards used to store the data). Discs are made from a 1.2 mm thick disc of   polycarbonate polycarbonate plastic,   with a thin layer of aluminium to make a reflective surface. The most plastic, common size of CD-ROM disc is 120 mm in diameter, though the smaller Mini CD standard with an 80 mm diameter, as well as numerous non-standard sizes and shapes (e.g., business card-sized media) are also available. Data is stored on the disc as a series of microscopic indentations. A laser is shone onto the reflective surface of the disc to read the pattern of pits and lands ("pits", with the gaps between them referred to as "lands"). Because the depth of the pits is approximately one-quarter to one-sixth of the wavelength of the laser light used to read the disc, the reflected beam's beam's phase is shifted in relation to the incoming beam, causing destructive causing destructive interference interference and reducing the reflected beam's intensity. This pattern of changing intensity of the reflected beam is converted into binary data.

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CPU (central processing unit) The Central Processing Unit (CPU) or the processor is the portion of a computer system that carries out the instructions of a computer a  computer program, program, and  and is the primary element carrying out the computer's functions. This term has been in use in the computer industry at least since the early 1960s. The form, design and implementation implementa tion of CPUs have changed dramatically since the earliest examples, but their fundamental operation remains much the same. Early CPUs were custom-designed as a part of a larger, sometimes one-of-a-kind, computer. However, this costly method of designing custom CPUs for a particular application has largely given way to the development of mass-produced processors that are made for one or many purposes. This standardization trend generally began in the era of discrete transistor mainframes and minicomputers and has rapidly accelerated with the popularization of the integrated the integrated circuit (IC). The IC has allowed increasingly complex CPUs to be designed and manufactured to tolerances on the order of nanometers. nanometers. Both  Both the miniaturization and standardization of CPUs have increased the presence of these digital devices in modern life far beyond the limited application of dedicated computing machines. Modern microprocessors appear in everything from automobiles from automobiles to cell to cell phones and children's toys. Functions of the CPU and its components(ALU, Control Unit e.t.c) CPU stands for central processing unit. Overall a personal computer can be divided into the following major parts from point of view v iew of functions performed: 1. Input devices (keyboard, mouse) 2. Output devices (monitor which displays the output or results of work being done on the computer) 3. CPU (central processing unit, which is the brain of the computer which does all the processing and calculations on data inputs and provides output on screen or

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printer) 4. Storage devices (memories, hard disk which store data). 5. Memory management 6. Interrupt handling Many times in common language the CPU term is used for the computer box unit which contains motherboard, processor, processor, hard disk, CD/DVD and floppy drives. This is the box to which we connect monitor, keyboard, mouse and printer through cables. In technical terms the term CPU is used only for the processor, which fits on the motherboard. Central Processing Unit (CPU), in computer science, microsc microscopic opic circuitry that serves as the main information processor in a computer. A CPU is generally a single microprocessor microproc essor made from a wafer of semiconducting material, usually silicon, with millions of electrical components on its surface. On a higher level, the CPU is actually a number of interconnected proces processing sing units that are each responsible for one aspect of the CPU's function. Standard CPUs contain processing units that interpret and implement software instructions, perform calculations and comparisons, comparison s, make logical decisions (determining if a statement is true or false based on the rules of Boolean algebra), temporarily store information for use by another of the CPU's processing units, keep track of the current step in the execution of the program, and allow the CPU to communicate with the rest of the computer. A CPU is similar to a calculator, only much more powerful. The main function of the CPU is to perform arithmetic and logical operations on data taken from memory or on information entered through some device, such as a keyboard, scanner, or  joystick. The CPU CPU is controlled controlled by a list of software instructions, instructions, called called a computer computer program. Software instructions entering the CPU originate in some form of memory storage device such as a hard disk, floppy disk, CD-ROM, or magnetic tape. These instructions then pass into the computer's main random access memory (RAM), where each instruction is given a unique address, or memory location. The CPU can access specific pieces of data in RAM by specifying the address of the data that it wants. As a program is executed, data flow from RAM through an interface unit of wires called the bus, which connects the CPU to RAM. The data are then decoded by a processing unit called the instruction decoder that interprets and implements software instructions. From the instruction decoder the data pass to the arithmetic/logic arithmetic/logi c unit (ALU), which performs calculations and comparisons. Data may be stored by the ALU in temporary memory locations called registers where it may be retrieved quickly. The ALU performs specific operations such as addition, multiplication, and conditional tests on the data in its registers, sending the resulting data back to RAM or storing it in another register for further use. During this process, a unit called the program counter keeps track of each successive instruction to make sure that the program instructions are followed by the CPU in the correct order.

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Control Unit A control unit in general is a central (or sometimes distributed but clearly distinguishable) part of whatsoever machinery that controls its operation, provided that a piece of machinery is complex and organized enough to contain any such unit. One domain in which the term is specifically used is the area of computer design. the motor automotive industry,   the control unit helps maintain various functionsIn of the motor the vehicle.  vehicle.industry,    Arithmetic Logic In computing, computing,   an arithmetic logic unit (ALU) is a digital circuit that performs arithmetic and logical operations. The ALU is a fundamental building block of the central processing unit (CPU) of a computer, and even the simplest simplest microprocessors  microprocessors contain one for purposes such as maintaining timers. The processors found inside modern CPUs and graphics processing units (GPUs)  (GPUs)  accommodate very powerful and very complex ALUs; a single component may contain a number of ALUs. Mathematician John von Neumann proposed the ALU concept in 1945, when he wrote a report on the foundations for a new computer called the EDVAC.  EDVAC.  Research into ALUs remains an important part of computer science, falling science, falling under Arithmetic and logic structures in the ACM the ACM Computing Classification Classification System. System.   3.4.6 File Management Systems A file system  system  (often also written as filesystem filesystem)) is a method of storing and organizing computer files and their data. Essentially, data. Essentially, it organizes these files into a database for the storage, organization, manipulation, and retrieval by the computer's operating computer's  operating system.  system.  File systems are used on data storage devices such as hard disks or CD-ROMs to maintain the physical location of the files. Beyond this, they might provide access to data on a file server by acting as clients for a  network protocol (e.g., NFS, (e.g., NFS, SMB,  SMB, or  or 9P clients), or they may be virtual and exist only as an access method for virtual data (e.g., procfs) (e.g., procfs).. It is distinguished from a directory a directory service and and registry.  registry.   Most file systems make use of an underlying data underlying data storage device that offers access to an array of fixed-size physical sectors, generally sectors, generally a power a power of 2 in size (512 bytes (512 bytes or 1, 2, or 4 KiB are most common). The file system is responsible for organizing these sectors into files into files and directories, and directories, and  and keeping track of which sectors belong to which file and which are not being used. Most file systems address data in fixedsized units called "clusters" "clusters" or "blocks"  "blocks"   which contain a certain number of disk sectors (usually 1-64). This is the smallest amount of disk space that can be allocated to hold a file. However, file systems need not make use of a storage

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device at all. A file system can be used to organize and represent access to any data, whether it is stored or dynamically generated (e.g., procfs) (e.g., procfs).. File names A file name (or name (or filename filename)) is a name assigned to a file in order to secure storage location in the or computer memory. Whether have the file system which has an underlying storage device not, file memory.  systems   typically directories associate file names with files, usually by connecting the file name to an index in a file allocation table of some sort, such as the FAT the FAT in a DOS a DOS file system, or an inode an inode in a Unix-like a Unix-like file system. Directory structures may be flat, or allow hierarchies where directories may contain subdirectories. In some file systems, file names are structured, with special syntax for filename extensions and version numbers. In others, file names are simple strings, and per-file metadata per-file metadata is stored elsewhere. Metadata Other bookkeeping information is typically associated with each file within a file system. The  The  length of the data contained in a file may be stored as the number of blocks allocated for the file or as an exact byte exact byte count. The time The time that the file was last modified may be stored as the file's timestamp. Some file systems also store the file creation time, the time it was last accessed, and the time the file's meta-data was changed. (Note that many early PC early  PC operating systems did not keep track of file times.) Other information can include the file's device type (e.g., block, character, block, character,   socket,   subdirectory,  socket, subdirectory,  etc.), its owner user-ID and group-ID,  group-ID,  and its access permission settings (e.g., whether the file is read-only, executable, read-only, executable, etc.).  etc.). Arbitrary attributes can be associated on advanced file systems, such as NTFS, as NTFS, XFS,  XFS,   ext2/ext3, ext2/ ext3,   some versions of UFS,  UFS,  and HFS+,  HFS+,  using extended file attributes.  attributes.  This feature is implemented in the kernels of Linux,  Linux,  FreeBSD and Mac OS X operating systems, and allows metadata to be associated with the file at the file system level. system level. This, for example, could be the author of a document, the character encoding of a plain-text document, or a checksum. a checksum.   Hierarchical file systems The hierarchical file system (not to be confused with Apple's Apple's HFS) HFS) was an early research interest of Dennis Ritchie of Unix fame; previous implementations were restricted to only a few levels, notably the IBM implementations, implementations, even of their early databases like IMS.  IMS.  After the success of Unix, Ritchie extended the file system concept to every object in his later operating system developments, such as Plan 9 and Inferno. and  Inferno.   Types of file systems

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File system types can be classified into disk file systems, network file systems and special purpose file systems. Disk file systems A disk file system is  files on a data a data storage system is a file system designed for the storage of  files device, device, most  most commonly a disk a disk drive, drive, which  which might be directly or indirectly connected to the computer. Examples of disk file systems include include FAT  FAT (FAT12, FAT16, FAT32, exFAT), NTFS, exFAT),  NTFS, HFS  HFS and HFS+, and HFS+, HPFS,  HPFS, UFS,  UFS,   ext2,  ext2,  ext3, ext3,   ext4, ext4,   btrfs,  btrfs,  ISO 9660,  9660,  ODS5, 5,   Veritas File System, VMFS, System, VMFS,   ZFS,  ZFS,  ReiserFS,  ReiserFS,  Linux SWAP and UDF. Some UDF. Some disk file systems are journaling are journaling file systems or versioning or versioning file systems.  systems.  ISO 9660 and Universal and Universal Disk Format are the two most common formats that target Compact Discs and DVDs. and DVDs. Mount  Mount Rainier is a newer extension to UDF supported by Linux 2.6 series and Windows Vista that facilitates rewriting to DVDs in the same fashion as has been possible with floppy disks. Flash file systems A flash file system  system  is a file system designed for storing files on flash memory devices. These are becoming more prevalent as the number of mobile devices is increasing, and the capacity of flash memories increase. While a disk file system can be used on a flash device, this is suboptimal for several reasons:  

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Erasing blocks: Flash memory blocks have to be explicitly erased before they can be rewritten. The time taken to erase blocks can be significant, thus it is beneficial to erase unused blocks while the device is idle. Random access:  access:  Disk file systems are optimized to avoid disk seeks whenever possible, due to the high cost of seeking. Flash memory devices impose no seek latency. Wear levelling: Flash levelling: Flash memory devices tend to wear out when a single block is repeatedly overwritten; flash file systems are designed to spread out writes evenly.

Log-structured file systems have many of the desirable properties for a flash file system. Such file systems include JFFS2 include  JFFS2 and YAFFS. and YAFFS.   Tape file systems A tape file system is system is a file system and tape format designed to store files on tape in a self-describing form. Magnetic tapes are sequential storage media, posing challenges to the creation and efficient management of a general-purpose file system. IBM has recently announced a new file system for tape called the Linear

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Tape File System. The IBM implementation of this file system has been released as the open-source IBM Long Term File System product. Database file systems A recent concept for file management is the idea of a database-based file system. Instead or in additionlike to, type hierarchical structured management, manag ement, files are  identified by their of, characteristics, of file, topic, author, or similar metadata. similar  metadata.  Transactional file systems Some programs need to update multiple files "all at once." For example, a software installation may write program binaries, libraries, and configuration files. If the software installation fails, the program may be unusable. If the installation is upgrading a key system utility, such as the command shell, command shell, the  the entire system may be left in an unusable state. Transaction processing introduces the isolation guarantee, which states that operations within a transaction are hidden from other threads on the system until the transaction commits, and that interfering operations on the system will be properly serialized with the transaction. Transactions also provide the atomicity guarantee, that operations inside of a transaction are either all committed, or the transaction can be aborted and the system discards all of its partial results. This means that if there is a crash or power failure, after recovery, the stored state will be consistent. Either the software will be completely installed or the failed installation will be completely rolled back, but an unusable partial install will not be left on the system. Windows, beginning with Vista, added transaction support to NTFS,  NTFS,  abbreviated TxF. TxF is the only commercial implementation of a transactional file system, as transactional file systems are difficult to implement correctly in practice. There are a number of research prototypes of transactional file systems for UNIX systems, including the Valor file system, Amino, LFS, and a transactional ext3 transactional  ext3 file system on the TxOS kernel, as well as transactional transactional file systems targeting embedded systems, such as TFFS. Ensuring consistency across multiple file system operations is difficult, if not impossible, without file system transactions. File locking can be used as a concurrency control mechanism for individual files, but it typically does not protect the directory structure or file metadata. For instance, file locking cannot prevent TOCTTOU race conditions on symbolic links. File locking also cannot automatically roll back a failed operation, such as a software upgrade; this requires atomi atomicity. city.

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Exercise 1. Give any two differences between machine code and assembly language [4marks]  

2. State and explain five functions of an operating system

[15marks]

3. State any five examples of an operating system

[5marks]

 

 

4. State and describe any three (3) secondary storage devices  

[12marks]

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3.5 Main Memory There are four major storage levels.  1. Internal  – Processor registers and cache. and cache.   2. Main – the system RAM system RAM and controller cards.  

 

 

3. On-line mass storage – Secondary storage. 4. Off-line bulk storage – Tertiary and Off-line and Off-line storage.  

There are different types of computer memory designated designated to store different types of data. They also have varied capabilities and specialties when it comes to storing essential information inside the computer. The best known computer memory is the RAM, also known as Random Access Memory. It's called random access because any stored data can be accessed directly if you know the precise row and column that intersect a certain memory cell. In this type of computer memory, memory, data can be

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accessed in any order. RAM’s exact opposite is called SAM or Serial Access Memory, which stores data in a series of memory cells that can only be accessed in order. It works very much like a cassette tape where you have to go through other memory cells before accessing the data that you're seeking.

The primary memory of a computer: it is random-access and stores the programs and data while they are being processed. It is volatile, meaning it loses all the data when the power is switched off. The primary storage section (also called internal   storage, main storage, main memory, or just memory) memory)  serves four purposes: . To hold data transferred from an I/O device to the input storage area, where it remains until the computer is ready to process it. To hold both the data being processed and the intermediate results of arithmetic-logic arithmetic-logi c operations. This is a working storage area  area  within storage section. It is sometimes referred to as a scratch pad memory. . To hold the processing results in an I/O device.

the the

output storage area  area  for transfer to an

To hold the program statements transferred from an I/O device. This area is called the program storage area.  area.  The Differences Between RAM and ROM Other types of computer memory include the ROM or Read Only Memory. ROM is an integrated circuit already programmed with precise data that can't be altered or changed, hence the name ―Read Only‖. There is also another type of computer memory called Virtual Memory. This type of memory is a common element in most operating systems and desktops. It helps the computers RAM to be freed up with inactive applications to make way for loading current applications being used. It works merely by checking for data stored in RAMnot being used recently and have it stored in the computer’s hard disk, thereby freeing useful space in RAM for

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loading other applications. A virtual memory will make a computer believe that it has nearly unlimited RAM inside it. Understanding Cache Memory Another type of computer memory that has made computers process tasks faster is what is known as cache Caches to relieveThis this isbottleneck by making the data used memory. most often by theare CPUconfigured instantly available. achieved by establishing a small amount of memory, known as primary or level 1 cache, right into the CPU. Level 1 cache is very small, normally ranging between 2 kilobytes (KB) and 64 KB. The secondary or level 2 cache usually resides on a memory card situated near the CPU. The level 2 cache has a direct connection to the CPU. A dedicated integrated circuit on the motherboard, the L2 controller, governs the use of the level 2 cache by the CPU. Depending on the CPU, the size of the level 2 cache ranges from 256 KB to 2 megabytes (MB). In most systems, data required by the CPU is accessed from the cache roughly 95 percent of the time, greatly reducing the overhead required when the CPU has to wait for data from the main memory.

Beyond operating system needs, the amount of RAM depends onneed the applications to be run. For instance, heavy graphics, realnecessary time video, and such more RAM to keep matters from slowing to a crawl or halt. Typically, off-the-rack machines come with 4 to 8MB, more than adequate for a general purpose computer. 3.5.2 Random access and sequential access Random Access In computer science, science,   random access  access  (sometimes called direct access) access) is the ability to access an arbitrary element of a sequence in equal time. The opposite is sequential access,  access,  where a remote element takes longer time to access. A typical illustration of this distinction is to compare an ancient scroll ancient scroll (sequential; all material prior to the data needed must be unrolled) and the book (random: can be immediately flipped open to any random page.  page.  A more modern example is a cassette tape (sequential— (sequential—you have to fast-forward through earlier songs to get to later ones) and a phonograph record (random access access— —you can place the needle right on the groove you want). In data In  data structures, random structures, random access implies the ability to access the N th th entry in a list of numbers in constant time. Very few data structures can guarantee this, other than arrays (and related structures like dynamic arrays). arrays). Random access is critical to many algorithms such as quicksort and binary search.  search.  Other data structures, such as linked lists,  lists,  sacrifice random access to make for efficient inserts, deletes, or reordering of data. Sequential Access

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In computer science, science,   sequential access  access  means that a group of elements (e.g. data in a memory array or a disk file or on a tape) is accessed in a predetermined, ordered sequence. Sequential access is sometimes the only way of accessing the data, for example if it is on a tape. It may also be the access method of choice, for example if we simply want to process a sequence of data elements in order. In data In data structures,   a data structure is said to have sequential access if one can only visit structures, the values it contains in one particular order. The canonical example is the linked list. Indexing list.  Indexing into a list that has sequential access requires O(k  O(k ) time, where k   is the index. As a result, many algorithms such as quicksort and binary search degenerate into bad algorithms that are even less efficient than their naïve alternatives; these algorithms are impractical without random without random access. On access. On the other hand, some algorithms, typically those that don't index, require only sequential access, such as mergesort, as mergesort, and  and face no penalty. 3.5.3 Access /Cycle times The average time lag between a request for information stored on a particular component, such as the hard drive or RAM, and its delivery.

Exercise 1. Highlight any three difference between the main memory and the backing storage [6marks]  

2. Explain the following memory access methods  

i) Sequential access ii) Random access [10marks] 3. Describe the following types of computer memory i) RAM ii) ROM iii) Cache [12marks]  

 

 

 

 

 

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3.6 Arithmetic Logic Unit (ALU) Arithmetic logic unit is that part of the computer which performs the different logic operations and arithmetic calculations like addition, subtraction, multiplication and division. It is the high speed digital circuit that solves calculations and does comparisons.

Functions of Arithmetic Logic Unit: •  Almost all the actions actions of the computer computer are done by it. It gets its data from a certain computer memory called processor register . After the data gets processed, its results get stored in output registers of the arithmetic logic unit . •  The arithmetic logic unit can perform integer arithmetic operations like addition, subtraction, etc. •  It can also perform bitwise logic operations operations like AND, OR, XOR, etc etc.. •  The arithmetic logic unit performs bit-shifting operations like rotating or shifting a certain word to either the left or the right by a given number of bits. These can also be represented as divisions by 2 and also multiplications by 2. These are the simple operations carried out by the arithmetic logic unit .

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In computing, computing,   an arithmetic logic unit  unit  (ALU ALU)) is a digital circuit that performs arithmetic and logical operations. The ALU is a fundamental building block of the central processing unit (CPU) of a computer, and even the simplest simplest microprocessors  microprocessors contain one for purposes such as maintaining timers. Most of a processor's operations are performed by one or more ALUs. An ALU loads data from input registers,  registers,  an external Control Unit then tells the ALU what operation to perform on that data, and then the ALU stores its result into an output register. Other mechanisms move data between these registers and memory.

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3.7 Computers Room Environment and Security Computer Room Environment IT operations are a crucial aspect of most organizational operations. One of the main concerns is business continuity; continuity; companies rely on their information systems to run their operations. If a system becomes unavailable, company operations may be impaired or stopped completely. It is necessary to provide a reliable infrastructure for IT operations, in order to minimize any chance of disruption. Information security is also a concern, and for this reason a data center has to offer a secure environment which minimizes the chances of a security breach. A data center must therefore keep high standards for assuring the integrity and functionality of its hosted computer environment. environment. This is accomplished through redundancy of both fiber optic cables and power, which includes emergency backup power generation. The physical environment of a data center is rigorously controlled. Air conditioning is used to control the temperature and humidity in the data center. ASHRAE's ASHRAE's "Thermal Guidelines for Data Processing Environments" recommends a temperature range of 16– 16–24 °C (61– (61–75 °F) and humidity range of 40– 40–55% with a maximum dew point of 15°C as optimal for data center conditions. The temperature in a data center will naturally rise because the electrical power used heats the air. Unless the heat is removed, the ambient temperature will rise, resulting in electronic equipment malfunction. By controlling the air temperature, the server components at the board level are kept within the manufacturer's specified temperature/humidity range. Air conditioning systems help control humidity by cooling the return space air below the dew point.  point.  Too much humidity, and water may begin to condense on internal components. In case of a dry atmosphere, ancillary humidification systems may add water vapor if the humidity is too low, which can result in static electricity discharge problems which may damage components. Subterranean data centers may keep computer equipment cool while expending less energy than conventional designs. Modern data centers try to use economizer cooling, where they use outside air to keep the data center cool. Washington state now has a few data centers that cool all of the servers using outside air 11 months out of the year. They do not use chillers/air conditioners, which creates potential potential energy savings in the millions. There are many types of commercially available floors that offer a wide range of structural strength and loading capabilities, depending on component construction and the materials used. The general types of raised floors include stringerless, stringered, and structural platforms, all of which are discussed in detail in GR-2930 and summarized below.

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Stringerless Raised Floors  Floors  - One non-earthquake type of raised floor generally consists of an array of pedestals that provide the necessary height for routing cables and also serve to support each corner of the floor panels. With this type of floor, there may or may not be provisionin provisioning g to mechanically fasten the floor panels to the pedestals. This stringerless type of system (having no mechanical attachments between the pedestal heads) provides

 

maximum the space the floor. floors are accessibility significantly to weaker than under stringered raisedHowever, floors in stringerless supporting lateral loads and are not recommended.  

Stringered Raised Floors Floors - This type of raised floor generally consists of a vertical array of steel pedestal assemblies (each assembly is made up of a steel base plate, tubular upright, and a head) uniformly spaced on two-foot centers and mechanically fastened to the concrete floor. The steel pedestal head has a stud that is inserted into the pedestal upright and the overall height is adjustable with a leveling nut on the welded stud of the pedestal head.

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Structural Platforms Platforms - One type of structural platform consists of members constructed of steel platform angles orfor channels that are welded or bolted together to form an integrated supporting equipment. This design permits equipmentt to be fastened directly to the platform without the need for toggle equipmen bars or supplemental bracing. Structural platforms may or may not contain panels or stringers.

Computer Security Computer Crime 1. unauthorized unauthorized use of a computer, which might involve stealing a username and password, or might involve accessing the victim's computer via the Internet through a backdoor operated by a Trojan Horse program.  

2. creating or releasing a malicious computer program (e.g., computer virus, worm, Trojan Horse).  

3. harassment harassment and stalking in cyberspace. 4. Using a computer, a scanner, graphics software, and a high-quality color laser or ink jet printer for forgery or counterfeiting is the same crime as using an old-fashioned printing press with ink.  

 

5. Stealing a laptop computer with proprietary information stored on the hard disk inside the computer is the same crime as stealing a briefcase that contains papers with proprietary information.  

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6. Using the Internet or online services to solicit sex is similar to other forms of solicitation of sex, and so is not a new crime.  

Computer Virus A computer virus is created when a programmer creates computer code that has the capability to replicate itself, hide, watch a certain to occur, and/or deliver a destructive or prankish payload onfor a disk or in event a computer program. Viruses can attach themselves to just about any type of file and are spread as infected files are used by other computers. Some viruses are relatively harmless, while others are very devastating. They can destroy files, software, program applications, and cause the loss of data. New computer viruses are constantly being created by malicious programmers. Because of this, it is vital to keep anti-virus software on computers up-to-date. Some anti-virus software programs allow users to set them to silently check for updates whenever users are connected to the Internet. Others remind users to periodically check for updates. Worms and Trojans are closely related viruses. A wormA makes of itselfthat on a computer, rather than infecting otherto files like viruses. Trojan copies is a program secretly installs itself on a computer and opens a back door to the computer so that malicious attacks can be remotely controlled. The actual Trojan is usually not damaging at first, but it is usually accompanied by other damaging programs. To protect your home computer against computer viruses, worms, and trojans, you should invest in anti-virus software, such as the software offered by Norton or McAfee. You should also make sure it stays up-to-date. Virus protection software on school computers is regularly updated by the school system network technicians. What Computer Viruses Infect Viruses can enter in many ways. virus Ahas entered a act system, it will generally hide computers until it is unknowingly run Once by theauser. virus will not until it has been run or some pre-established condition has been met, such as a specific date. The effects of a virus may not be noticed for some time after it has infected a computer. Viruses can infect several components of a computer's operating and file system including:  

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System Sectors/Boot Records Records - Viruses can infect the parts of the system that are used to run programs and perform functions such as start up and shut down. Files Files  - Viruses can infect program files. These viruses stick to program files such as .com, .exe, .sys, etc. Some viruses hide in the memory of

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the computer at first, while others simply attack a specific software program, such as Microsoft Word. Companion Files  Files  - Viruses can create companion files that are a special type of file that adds files fi les that run on the hard disk. Macros Macros  - Viruses can infect macro or data files. Disk Clusters Clusters - Viruses can infect files through the disk directory.

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Batch Files Files  - Viruses can can use batch to infect a computer. Source Code Code    - Viruses be in files additional code that is added to actual program source code. Visual Basic Worms  Worms  - These worms use the Visual Basic programming language to control a computer and perform tasks.

Types of Computer Viruses Viruses are categorized by how they infect computers. Some viruses fall into more than one of these t hese categories. Types of viruses include:  

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Polymorphic Viruses - Polymorphic Viruses Polymorphic viruses change characteristics characteristics as they infect a computer. Stealth Viruses - Stealth viruses actively try to hide themselves from anti-virus and system software. Fast and Slow Infectors - Fast and Slow viruses infect a computer in a particular way to try to avoid being detected by anti-virus software. Sparse Infectors Infectors - Sparse Infectors don't infect very often. Armored Viruses  Viruses  - Armored viruses are programmed to make eradication difficult. Multipartite Viruses  Viruses  - Multipartite Viruses are viruses that may fall into more than one of these categories. Cavity (Spacefiller) Viruses Viruses - Cavity (Spacefiller) viruses attempt to maintain a constant file size when infecting a computer in order to try to avoid detection. Tunneling Viruses  - Tunneling viruses try to "tunnel" under antiViruses  virus software while infecting. Camouflage Viruses  Viruses  - Camouflage viruses attempt to appear as a benign program. Virus Droppers Droppers - Virus Droppers are a special category of programs that place viruses on computers but are not by themselves an actual virus.

Ways to Catch a Computer Virus There are several ways to catch a computer virus:

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From Floppy Disks Disks - Be very careful about putting a floppy disk that has been in another computer in your computer, even if it is from a trusted source. From the Internet  Internet  - Viruses can be attached to various types of Internet files, such as graphics and program files that people download from the Internet. Just browsing the Internet does not put your computer risk.a You have to download and install a file for a virus to be able to at infect computer. From E-Mail - Viruses often travel via e-mail attachments. E-mail messages by themselves do not carry viruses. Only .exe, .com or other types of executable files can carry a virus. From a Computer Network  Network  - Computer Networks are groups of computers linked together by a large computer called a server. The server and these computers constantly share information. If one file that is used by several network users becomes infected with a virus, the virus will quickly spread to the other users.

Symptoms of a Computer Virus The following are somecan possible indications that a computer has been a virus. These problems also be caused by non-virus problems, but infected they areby the most reported symptoms of a computer virus infection.        

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Computer programs take longer to load than normal. The computer's hard drive constantly runs out of free space. The floppy disk drive or hard drive runs when you are not using it. New files keep appearing on the system and you don't know where they came from. Strange sounds or beeping noises come from the computer or keyboard. Strange graphics are displayed on your computer monitor. Files have strange names you don't recognize. You are unable to access the hard drive when booting from the floppy drive. Program sizes keep changing. Conventional memory is less than it used to be and you can't explain it. Programs act erratically.

Safe Computing Practices There are several things you can do the help protect your computer against viruses:  

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Anti-Virus Software  Software  - If you don't have an anti-virus software program, invest in one.

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Scan Your Computer on a Regular Basis  Basis   - Scan you system with anti-virus software regularly. Update Your Anti-Virus Software on a Regular Basis Basis  - Keep your anti-virus software up to date. Do this at least weekly and more often if there are news reports of a new virus threat. Backup Backup  - Backup your files on a regular basis. Always maintain copies of you can't do without, just in case your computer gets infected andfiles crashes. Turn off E-Mail Preview  Preview  - Turn off the preview function if your email software has one. Scan Floppy Disks  Disks  - Scan floppy disks from other computers with anti-virus software before you use the disk. Simply place the disk in your floppy drive and run the anti-virus software program. If a virus is found, most programs will give you several choices about what to do, such as removing the virus, doing nothing, or deleting the file that contains the virus. Protect Your Floppy Disks Disks - Write-protect any floppy disk you place into another computer. If the other computer has a boot sector virus, the write-protect on the disk will prevent it from becoming infected with the virus. Scan Downloaded Files Files - Scan downloaded Internet files with antivirus software before you use or run them. Scan All E-Mail Attachments  Attachments  - If you receive an attachment you need to view, scan it with anti-virus software before you open it. Beware of E-Mail Attachments from Unknown Sources  Sources   - If you receive an unexpected attachment from an unknown source, delete it. Never open attachments for files that end in .vbs (Visual Basic Script) or .js (Java Script). Viruses often travel in these types of files. Be Alert Alert - Pay attention to news about virus alerts. You might want to subscribe to a virus alert e-mail notice from one of the anti-virus software makers.

Exercise 1. The use of computers have health effects on the users. Outline any five (5) health effects. [10marks]  

2. a) What is a computer virus?  

[2marks]

b) Identify any four (4) indicators indicators that sho show w the presence presence of a virus on a computers. [8marks] 3. Give five (5) requirements of a computer environment (computer room) [10marks]

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3.8 Data Processing Data processing  processing  is any process that uses a  a  computer program to enter data and summarise, analyse or otherwise convert otherwise convert data into usable information. The information. The process may be automated and run on a computer. a  computer. It  It involves recording, analysing, sorting, summarising, calculating, disseminating and storing data. Because data is most useful when well-presented and actually informative informative,, data-processing systems are often referred to as information systems.  systems.  Nevertheless, the terms are roughly synonymous, performing similar conversions; data-processing systems typically manipulate raw data into information, and likewise information systems typically take raw data as input to produce information as output. Data processing may or may not be distinguished from data conversion,  conversion,  when the process is merely to convert data convert data to another format, another format, and  and does not involve any data any data manipulation.   manipulation. Data Processing (DP) makes use of powerful computer systems to collect and process large volumes of data at high speed. Most large companies and organisations use a mainframe computer which processes data very quickly and can store vast amounts of data that large companies require. Banks and other organisations deal with millions of pieces of data each day. DP is used for:              

Stock control – keeping track of what a shop has to sell. Calculating wages and making up payslips Keeping track of orders Producing invoices Monitoring payments and withdrawals Processing application forms Producing statements

DP makes it possible for businesses to keep accurate, up-to-date records of thousands of customers that can be accessed straight away. This ensures that a company operates as efficiently as possible. Advantages of Electronic Data Processing (i) Data is processed much more quickly than in a manual system. (ii) Errors are much less likely – data is more accurate.

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(iii) It is easier to store large amounts of data than with a manual system. (iv) Information can be accessed very quickly and by many people at the same time. (v) Computer systems do repetitive tasks without getting bored, slowing down or making error Data processing cycle

Storage

Origination of Data

Preparation of

Output

CONTROL

Processing

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Input of Data

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Data origination Data origination  origination  is the process of transferring data between storage types, formats, or computer systems.  systems.  Data origination is usually performed programmatically to achieve an automated migration, migration, freeing up human resources from tedious tasks. It is required when   organizations or individuals change computer systems or upgrade to new systems, or when systems merge (such as when the organizations that use them undergo a merger or takeover). To achieve an effective data migration procedure, data on the old system is mapped to the new system providing a design for data for data extraction and data and data loading.  loading.  The design relates old data formats to the new system's formats and requirements. Programmatic data origination may involve many phases but it minimally includes data extraction  extraction  where data is read from the old system and data loading  loading  where data is written to the new system. If a decision has been made to provide a set input file specification for loading data onto the target system, this allows a pre-load 'data validation' step to be put in place Preparation of Data Basically involves Data Verification and Data validation Data Verification  Verification  is a process wherein the data is checked for accuracy and inconsistencies inconsistenc ies after data origination is done. It helps to determine whether data was accurately translated, is complete, and supports processes processes in the new system. During verification, there may be a need for a parallel run of both systems to identify areas of disparity and forestall erroneous data loss. Data validation  validation  is the process of ensuring that a program operates on clean, correct and useful data. It uses routines, often called "validation rules"  rules"  or "check routines", that check for correctness, meaningfulness, and security of data that are input to the system. The rules may be implemented through the automated facilities of a data dictionary,  dictionary,  or by the inclusion of explicit application program validation logic. For business applications, data validation can be defined through declarative data integrity rules, or procedure-based business rules.  rules.  Data that does not conform to these rules must negatively affect business process execution. Therefore, data validation should start with business process definition and set of business rules within this process. Rules can be collected through the requirements capture exercise.

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The simplest data validation verifies that the characters provided come from a valid set. For example, telephone numbers should include the digits and possibly the characters +, -, (, and) (plus, minus, and parentheses). A more sophisticated data validation routine would check to see the user had entered a valid country code, i.e., that the number of digits entered matched the convention for the country or area specified. Incorrect data validation can lead to data corruption or a security vulnerability.  vulnerability.  Data validation checks that data are valid, sensible, reasonable, and secure before they are processed. Data Processing In this step the input data are changed, and usually combined with other information, to produce data is more useful form. Thus, paychecks may be calculated from the time cards, or a summary of sales for the month maybe calculated from the sales orders. The processing step usually involves a sequence of certain basic processing operations.  operations.  Output Here results of depends the preceding processin g steps are collected. The particular form of thethe output data on theprocessing use of data.  data.   Storage Data is stored in some secondary memory storage awaiting future use or to be communicated communi cated to other areas were it is suppose to be used as feedback or as input. Validation methods Allowed character checks Checks that ascertain that only expected characters are present in a field. For example a numeric field may only allow the digits 0-9, the decimal point and perhaps a minus sign or commas. A text field such as a personal name might disallow characters such as < and >, as they could be evidence of a markup-based markupbased security attack. An e-mail address might require exactly one @ sign and various other structural details. Regular details. Regular expressions are effective ways of implementing such checks. (See also data type checks below) Batch totals Checks for missing records. Numerical fields may be added together for all records in a batch. The batch total is entered and the computer checks that the total is correct, e.g., add the 'Total Cost' field of a number of transactions together.

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Cardinality check Checks that record has a valid number of related records. For example if Contact record classified as a Customer it must have at least one associated Order (Cardinality > 0). If order does not exist for a "customer" record then it must be either changed to "seed" or the order must be created. This type of rule can be complicated by additional conditions. For example if contact record in Payroll database is marked as "former employee", then this record must not have any associated salary payments after the date on which employee left organisation (Cardinality = 0). Check digits Used for numerical data. An extra digit is added to a number which is calculated from the digits. The computer checks this calculation when data are entered, e.g., The ISBN for a book. The last digit is a check digit calculated modulus calculated  modulus 11. Consistency checks Checks fields to ensure data in these fields corresponds, e.g., If Title = "Mr.", then Gender = "M". Control totals This is a total done on one or more numeric fields which appears in every record. This is a meaningful total, e.g. e.g.,, add the total payment for a number of Customers. Cross-system consistency checks Compares data in different systems to ensure it is consistent, e.g., The address for the customer with the same id is the same in both systems. The data may be represented differently in different systems and may need to be transformed to a common format to be compared, e.g., one system may store customer name in a single Name field as 'Doe, John Q', while another in three different fields: First_Name (John), Last_Name (Doe) and Middle_Name (Quality); to compare the two, the validation engine would have to transform data from the second system to match the data from the first, for example, using SQL: Last_Name || ', ' || First_Name || substr(Middle_Name, 1, 1) would convert the data from the second system to look like the data from the first 'Doe, John Q' Data type checks

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Checks the data type of the input and give an error message if the input data does not match with the chosen data type, e.g., In an input box accepting numeric data, if the letter 'O' was typed instead of the number zero, an error message would appear. Exercise 1. State and explain the five(5) stages of the data processing cycle. [10marks] 2. Give four advantages of electronic data processing [5marks]  

 

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3.9 Software Delivery Computer software, software, or just software software,, is the collection of  computer   computer programs and related data related  data that provide the instructions telling a computer a  computer what to do and how to do it. We can also say software refers to one or more computer programs and data held in the storage of the computer for some purposes. Program software Program  software performs the function of the  the  program it implements, either by directly providing instructions to the computer hardware or by serving as input to another piece of software. The term was coined to contrast to the old term hardware (meaning physical devices). In contrast to hardware, software is intangible, meaning it "cannot be touched". Software is also sometimes used in a more narrow sense, meaning application software only. Sometimes the term includes data that has not traditionally been associated with computers, such as film, tapes, and records.  records.   Choosing software Software Buyer’s Checklist    

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How long has the company been around? Has it delivered its promises?

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What is the price?

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How steep is the learning curve? How easily can the software be integrated with existing systems?

 

Is its navigation & interface familiar with other software used?

 

Is my data safe?

 

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Factors to consider when choosing software Features: What does the software do? Can it do the things you need it to do?; Fit: How will the software fit in with other products that you use, and with your organisation's IT strategy?; Futures: Where is the market going? Is this product going to leave you in a proprietary niche or without support?; Flexibility: What changes can you foresee for your organization? Do you need to plan for different needs or working practices? Funds: What's your budget? Can you afford the product, the licenses, the training, the upgrades?

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Good Support Practices -

Availability of human help Quality of execs’ support Well documented help engine Free training sessions

Low Maintenance, High Performance Performance ? Needs special support staff? ? How reliable is it? ? Is it updated regularly? ? Are bugs fixed? Security is a top consideration because in many cases the software company will be handling information critical to us –  business, financial or personal data.”

Better Safe than Sorry ? What encryption standard is used? ? Is the data regularly backed up? ? What is their past record like? ? Is their server system modern? - Company Background -

Technical Factors Ease of Use Familiarity Security

Types of software System software System software provides the basic functions for computer usage and helps run the computer hardware computer  hardware and system. It includes a combination of the following:          

device drivers operating systems servers utilities window systems

System software is responsible for managing a variety of independent hardware components, so that they can work together harmoniously. Its purpose is to unburden the application software programmer from the often complex details of

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the particular computer being used, including such accessories as  as   communications devices,   printers, device devices, printers, device readers, displays and keyboards, and also to partition the computer's resources such as memory and processor time in a safe and stable manner.

Programming software  software  Programming software usually provides tools to assist a programmer in writing computer programs,  programs,  and software using different programming languages in a more convenient way. The tools include:          

compilers debuggers interpreters linkers text editors

An  Integrated development environment (IDE) is a single application that attempts An  to manage all these functions. Application software System software does not aim at a certain application fields. In fields. In contrast,different application software offers different functions based on users and the area it served. Application served.  Application software is developed for some certain purpose, certain purpose,which which either can be a certain program or a collection of some programmes,such programmes, such as a graphic browser or the data base management system.  system.  Application software allows end users to accomplish one or more specific (not directly computer development related) tasks. related)  tasks. Typical  Typical applications include:  

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industrial automation business software video games quantum chemistry chemistry and solid state physics software telecommunications (i.e., the (i.e., the Internet and everything that flows on it) databases educational software Mathematical software medical software molecular modeling software image editing spreadsheet simulation software Word processing

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Decision making software

Advantages and disadvantages of: Integrated software Integrated software  software  is software for personal computers that combines the most commonly used functions of many productivity software programs into one application.The integrated software genre has been largely overshadowed by fully functional office suites,  suites,  most notably Microsoft Office. Office.   The integrated software market of today is exemplified by entry-level programs such as Microsoft Works which are often bundled with personal computers as "starter" productivity suites. Advantages 1. When you purchase the product, you get everything you need all at the same time. 2. They will work together quite efficiently to help you create quality documents (for example you can embed Excel charts in Word or Powerpoint documents. Or you can import Excel tables into Access (for databases).) 3. Standard GUI - learn one and you've got a great head start on the others. 4. The programs are smaller and all applications are together making it easier to use. 5. Assists users in performing a number of interrelated tasks such as word processing,, presentations, spreadsheets and data base management etc. processing 6. By selling the software in packages, it will save the users the hassle of installing the software one by one. Disadvantages 1. You can't upgrade (or fix) just one part, as all the software is intergrated into one application. 2. Another problem with intergrated software is that they usually have have weak areas, meaning that they may have a brilliant word processing application, but a below average spreedsheet program. 3. it also tend to lean towards the idea that because there are multiple programs and utility software all complied together, they don't tend to specialise in one section. When you have one company trying to improve lots of different programs at once, the individual programs tend advance at different rates. Though this shouldn't be the case with multiple companies supporting the intergrated software set. 4. And to add it is also memory hungry, it takes up more space than an  

 

 

 

average package

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Off the shelf software Commercial, off-the-shelf   (COTS COTS)) or simply off the shelf   (OTS OTS)) is a term defining technology which is ready-made and available for sale, lease, or license to the general public. The term often refers to computer software or hardware systems and may also include free software with commercial support. COTS purchases are alternatives to in-house developments or one-off   government-funded developments.  COTS typically requires configuration that is tailored for specific developments.  uses. The use of COTS has been mandated across many government and business programs, as such products may offer significant savings in procurement, development,, and maintenance. development Advantages  

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The software tends to be relatively cheap as the cost of development can be spread over a large number of users The software can be very sophisticated (e.g. Excel or Word) as the revenues from a very large numbers of users means that a lot of resources can be applied to it's development It is easy to get support and literature is usually widely available as there are many other users using exactly the same software It is easy to share files produced by the software with others as chances are they also have the software available to open the file You don't have to dedicate any of your time to the development process (e.g. helping with specifications, testing etc.)

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The software can be highly complex and will usually include large sections that you will never use (the average Word user is reputed to only use about 10% of the available facilities). It tends to be a compromise. By it's nature it is designed for many different types of users, each of whom will have different requirements As the software tends to be large and complicated it may take a long time to learn properly (some of the most asked for additions to later versions of Word were ones that already existed ex isted in the previous version!) You may have to alter the way that you work in order to fit in with the way that the software has been designed There will probably be operations that you require that you simply cannot do with the software As one small voice amongst many others your requests will not carry much weight If you have problems you are usually at the mercy of a large and faceless organisation who may not be quite as concerned as you are if you have a major problem that absolutely MUST be fixed before tomorrow morning morning!!

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As the same system can be bought by your competitors it is very difficult to gain any competitive advantage from it's use

In-house software In-House development means that a company has programmers on its staff and develops software internally. When a company needs a piece of software written they sometimes choose to use programmers within their own company to write it. Advantages  

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It has been specifically designed for your particular requirements and can be tailored to fit in exactly with the way that your business or organisation wishes to operate. It can be customised to interface with other software that you operate with the potential to provide you with a fully integrated IT infrastructure across your whole organisation Users will usually find it easier and more intuitive to use as it should not contain unnecessary or superfluous facilities and should operate in the way that they are used to working It is much more flexible than packaged software and can be modified and changed over time as your requirements and business practices change You will receive much better support and can in many cases talk directly to the developers concerned If you are lucky and find a good developer then they can significantly add value to your company by suggesting alternatives, improvements and by acting as a source of IT advice and information The use of professionally developed bespoke software applications can give you a significant business advantage over your competition As an alternative to the point above, you have the option, assuming you own the rights to the application to sell the application to others and recoup some or all of your investment.

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If you pick the wrong developer you could end up with an application that is unstable, unreliable and full of bugs (but then again so is some packaged software!). Selecting a developer who works to Best Practice and industry standards should counteract this. The investment required will usually be much higher than with packaged software. This is usually the biggest reason for not going down the custom route - you need to undertake a business justification exercise and compare the costs against the expected benefits and commercial commercial advantages. A large investment in your time is required during the development process and a bespoke application will take longer to implement. implement.

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An unacceptable proportion of developers are either incompetent, unprofessional or are 'cowboys' and it can be difficult to sort out the good guys from the bad.

Contracted software Contracted software operates on the basis of mutual obligations obligations and  and benefits benefits.. The metaphor comes from business life, where a "client" and a "supplier" agree on a "contract" which defines for example that:  

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The supplier must provide a certain product (obligation) and is entitled to expect that the client has paid its fee (benefit). The client must pay the fee (obligation) and is entitled to get the product (benefit). Both parties must satisfy certain obligations, such as laws and regulations, applying to all contracts.

Tailor made software Tailor made or Custom software  software  (also known as bespoke software) software) is software that is specially is specially developed for some specific organization or other user. As such it can be contrasted with the use of software packages developed for the the mass  mass market,   such as commercial off-the-shelf (COTS) software, or existing free market, software. Custom software.  Custom software can be developed by an in-house software development group, or be commissioned from a software house or independent software developer.   Large companies commonly use custom software for critical functions, developer. including content management,  management,  inventory management,  management,  customer management,  management,  human resource management,  management,  or otherwise to fill needs that existing software packages cannot. Often such software is legacy software,  software,  developed before COTS software packages offering the required functionality became available. Advantages  

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It has been specifically designed for your particular requirements and can be tailored to fit in exactly with the way that your business or organisation wishes to operate. It can be customised to interface with other software that you operate with the potential to provide you with a fully integrated IT infrastructure across your whole organisation Users will usually find it easier and more intuitive to use as it should not contain unnecessary or superfluous facilities and should operate in the way that they are used to working It is much more flexible than packaged software and can be modified and changed over time as your requirements requirements and business practices change You will receive much better support and can in many cases talk directly to the developers concerned

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If you are lucky and find a good developer then they can significantly add value to your company by suggesting alternatives, improvements and by acting as a source of IT advice and information The use of professionally developed bespoke software applications can give you a significant business advantage over your competition As an alternative to the point above, you have the option, assumi assuming ng you own

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the rights to the application to sell the application to others and recoup some or all of your investment. Disadvantages If you do not have the source code you are dangerously exposed and are wholly dependent upon the developer's continuing existence and good will. To avoid this problem make sure you choose a developer who provides you with the source code. If you pick the wrong developer you could end up with an application that is unstable, unreliable and full of bugs (but then again so is some packaged software!). Selecting a developer who works to Best Practice and industry standards should counteract this.

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The investment willbiggest usuallyreason be much higher than withthe packaged software. This is required usually the for not going down custom route - you need to undertake a business justification exercise and compare the costs against the expected benefits and commercial commercial advantages. A large investment in your time is required during the development process and a bespoke application will take longer to implement. It can be difficult to get support for bespoke software, unless the developers themselves offer support services. An unacceptable proportion of developers are either incompetent, unprofessional or are 'cowboys' and it can be difficult to sort out the good guys from the bad.

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Exercise 1. State and describe the two major types of software [8marks] 2. Give advantages and disadvantages of the following types of application software i) Off the shelf software ii) Tailor made software iii) In house software [12marks] 3. Highlight any five (5) factors you would consider when choosing software [10marks]  

 

 

 

 

 

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3.10 Communication System Basics What is a Network? A network consists of two or more computers that are linked in order to share resources (such as printers and CDs), exchange files, or allow electronic communications. The computers on a network may be linked through cables, telephone lines, radio waves, satellites, or infrared light beams. The two basic types of networks include:    

Local Area Network (LAN) Wide Area Network (WAN)

You may also see references to a Metropolitan Area Networks (MAN), a Wireless LAN (WLAN), or a Wireless WAN (WWAN). Local Area Network A Local Area Network (LAN) is a network that is confined to a relatively small area. It is generally limited to a geographic geographic area such as a writing lab, school, or building. Rarely are LAN computers more than a mile apart. In a typical LAN configuration, one computer is designated as the file server. It stores all of the software that controls the network, as well as the software that can be shared by the computers attached to the network. Computers connected to the file server are called workstations. The workstations can be less powerful than the file server, and they may have additional software on their hard drives. On many LANs, cables are used to connect the network interface cards in each computer; other LANs may be wireless. See the Topology,  Topology,  Cabling,  Cabling,  and Hardware sections of this tutorial for more information on the configuration of a LAN. Wide Area Network Wide Area Networks (WANs) connect larger geographic areas, such as Florida, the United States, or the world. Dedicated transoceanic cabling or satellite uplinks may be used to connect this type of network. Using a WAN, schools in Florida can communicate communicate with places like Tokyo in a matter of minutes, without paying enormous phone bills. A WAN is complicated. It uses multiplexers to connect local and metropolitan networks to global communications networks like the Internet. To users, however, a WAN will not appear to be much different than a LAN.

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Advantages of Installing a Network  

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Speed. Networks provide a very rapid method for sharing and transferring Speed. files. Without a network, files are shared by copying them to memory cards or discs, then carrying or sending the discs from one computer to another. This method of transferring files (referred to as sneaker-net) sneaker-net) can be very time-consuming. Cost.. Networkable versions of many popular software programs are available Cost at considerable savings when compared to buying individually licensed copies. Security.. Files and programs on a network can be designated as "copy Security inhibit," so that you do not have to worry about illegal copying of programs. Also, passwords can be established for specific directories to restrict access to authorized users. Centralized Software Management. Management. One of the greatest benefits of installing a network is the fact that all of the software can be loaded on one computer (the file server). This eliminates that need to spend time and energy installing updates and tracking files on independent computers throughout the building. Resource Sharing Sharing. resources another fax advantage of networks. Most schools cannot. Sharing afford enough laseris printers, machines, modems, scanners, and CD players for each computer. However, if these or similar peripherals are added to a network, they can be shared by many users. Electronic Mail. Mail. The presence of a network provides the hardware necessary to install an e-mail system. E-mail aids in personal and professional communication for all personnel, and it facilitates the dissemination dissemina tion of general information to the entire school staff. Electronic mail on a LAN can enable students to communicate with teachers and peers at their own school. If the LAN is connected to the Internet, students can communicate commun icate with others ot hers throughout the world. Flexible Access. Access. College networks allow students to access their files from computers throughout the school. Students can begin an assignment in their classroom, save part of school it on a public access of Students the network, to the media center after to finish theirarea work. can then also go work cooperatively cooperative ly through the network. Workgroup Computing. Computing. Collaborative software allows many users to work on a document or project concurrently. For example, educators located at various schools within a county could simultaneously contribute their ideas about new curriculum standards to the same document, spreadsheets, or website.

Disadvantages of Installing a School Network  

Expensive to Install. Install. Although a network will generally save money over time, the initial costs of installation can be prohibitive. Cables, network cards,

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routers, and software are expensive, and the installation may require the services of a technician. Requires Administrative Time. Time. Proper maintenance of a network requires considerable considerabl e time and expertise. Many schools have installed a network, only to find that they did not budget for the necessary administrati administrative ve support. File Server May Fail. Fail. Although a file server is no more susceptible to failure than any other computer, when the files server "goes down," the entire network may come to a halt. When this happens, the entire school may lose access to necessary programs and files. Cables May Break. Break. The Topology chapter presents information about the various configurations of cables. Some of the configurations are designed to minimize the inconvenience of a broken cable; with other configurations, configurations, one broken cable can stop the entire network. Must Monitor Security Issues. Issues . Wireless networks are becoming increasingly common; however, security can be an issue with wireless networks.

Network Hardware Network Interface Cards The network interface card (NIC) provides the physical connection between the network and the computer workstation. Most NICs are internal, and they are included in the purchase of most computers. Network interface cards are a major factor in determining the speed and performance of a network. It is a good idea to use the fastest network card available for the type of workstation you are using. The most common network interface connections are Ethernet cards (LocalTalk connectors and Token Ring cards are seldom used in current networks). Ethernet Cards Ethernet cards are usually purchased separately from a computer, although many computers (such as the Macintosh) now include an option for a pre-installed Ethernet card. Ethernet cards contain connections for either coaxial or twisted pair cables (or both) (See fig. 1). If it is designed for coaxial cable, the connection will be BNC. If it is designed for twisted pair, it will have a RJ-45 connection. Some Ethernet cards also contain an AUI connector. This can be used to attach coaxial, twisted pair, or fiber optics cable to an Ethernet card. When this method is used there is always an external transceiver attached to the workstation. (See the Cabling section for more information on connectors.)

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LocalTalk Connectors LocalTalk is Apple's built-in solution for networking older Macintosh computers. It utilized a special adapter box and a cable that plugged into the printer port of a Macintosh. A major disadvantage of LocalTalk was that it is slow (only 230 Kbps) in comparison to Ethernet; therefore, it is rarely used in current networks. Token Ring Cards Token Ring network cards look similar to Ethernet cards and were popular in IBM computers. They are seldom used with current networks.

Switches A concentrator is a device that provides a central connection point for cables from workstations, servers, and peripherals. In a star topology, twisted-pair wire is run from each workstation to a central switch/hub. Most switches are active, that is they electrically amplify the signal as it moves from one device to another. Switches no longer broadcast network packets as hubs did in the past, they memorize addressing of computers and send the information to the correct location directly. Switches are:          

Usually configured with 8, 12, or 24 RJ-45 ports Often used in a star or tree topology Sold with specialized software for port management Also called hubs Usually installed in a standardized metal rack that also may store netmodems, bridges, netmodems,  bridges, or  or routers  routers

Repeaters Since a signal loses strength as it passes along a cable, it is often necessary to boost the signal with a device called a repeater. The repeater electrically amplifies the signal it receives and rebroadcasts it. Repeaters can be separate devices or they can be incorporated into a concentrator. They are used when the total length of your network cable exceeds the standards set for the type of cable being used. A good example of the use of repeaters would be in a local area network using a star topology with unshielded twisted-pair cabling. The length limit for unshielded twisted-pair cable is 100 meters. The most common configuration is for each workstation to be connected by twisted-pair cable to a multi-port active concentrator. The concentrator concentrator amplifies all the signals that pass through it allowing for the total length of cable on the network to exceed the 100 meter limit.

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Bridges A bridge is a device that allows you to segment a large network into two smaller, more efficient networks. If you are adding to an older wiring scheme and want the new network to be up-to-date, a bridge can connect the two. A bridge monitors the information traffic on both sides of the network so that it can pass packets of information to the correct location. Most bridges can "listen" to the network and automatically figure out the address of each computer on both sides of the bridge. The bridge can inspect each message and, if necessary, broadcast it on the other side of the network. The bridge manages the traffic to maintain optimum performance on both sides of the network. You might say that the bridge is like a traffic cop at a busy intersection during rush hour. It keeps information flowing on both sides of the network, but it does not allow unnecessary traffic through. Bridges can be used to connect different types of cabling, or physical topologies.  topologies.  They must, however, be used between networks with the same protocol. same protocol.   Routers A router translates information from one network to another; it is similar to a superintelligent bridge. Routers select the best path to route a message, based on the destination address and origin. The router can direct traffic to prevent head-on collisions, and is smart enough to know when to direct traffic along back roads and shortcuts. While bridges know the addresses of all computers on each side of the network, routers know the addresses of computers, bridges, and other routers on the network. Routers can even "listen" to the entire network to determine which sections are busiest -- they can then redirect data around those sections until they clear up. If you have a school LAN that you want to connect to the Internet, the  Internet, you  you will need to purchase a router. In this case, the router serves as the translator between the information on your LAN and the Internet. It also determines the best route to send the data over the Internet. Routers can:        

Direct signal traffic efficiently Route messages between any two protocols Route messages between linear between linear bus, star, bus, star, and  and star-wired  star-wired ring topologies Route messages across fibre across fibre optic, coaxial, optic, coaxial, and  and twisted-pair  twisted-pair cabling

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Network Topologies Network topology refers to the geometric arrangement or physical layout of computers, peripherals and cable links in a network. There are three primary topologies:  

Bus Star  Ring The Bus Topology  

 

 

The bus topology is the simplest and most commonly used topology for networking computers. It is also known as a linear bus because computers are attached of connected to a single linear cable called a trunk or backbone. Computers on the bus network communicate by sending packets of data to each other. A computer will send a packet of data to all computers on the network (broadcast). Each computer listens and examines every packet on the wire to determine if the packet is intended for it, and accepts only packets addressed to it. The bus topology is a passive topology because computers on the network are not actively involved in the movement of data. On an active topology computers regenerate the data signals and pass the signal to the next computer on the network. The number of computers on the network affects network performance. Performance degrades as more computers are added to the bus network.

Backbone/trunk

Terminator 

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Advantages It uses the least amount of cable and is easy to expand.  It is relatively simple, inexpensive and reliable.  Failure of one does not bring the whole network down. Disadvantages  

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A cable break can bring the entire network down. Network becomes slower and slower as more and more computers are added to the network. It is difficult to troubleshoot and isolate problems.

Star Topology On a star topology, each computer is connected by cable segment to a central device, which can be a hub, switch or repeater. Computers communicate with each other by passing data through the hub. The network requires more cables because each computer requires a cable segment to connect to the central device. If a computer fails or the cable segment that connects the computer to the hub is broken, only that link is affected the rest of the network continues to function normally.

Repeater, Hub, Switch

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Network expansion and reconfiguration are relatively simple. For instance, new computers can easily be added to the network. Failure of one computer does not affect the rest of tthe he network. Each computer is attached by its own cable segment to the central hub, which makes it easy to isolate individual computers from the network by disconnecting disconnec ting them from the wiring hub. Can accommodate different wiring.

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Disadvantages  Uses a large amount of cable because each computer must have a separate cable run from the central device.  If the central device fails, the entire network fails.  

 

Ring Topology On a ring topology, computers are connected one node to other by a single cable forming a circle. Computers on the ring network use a signal called a token to carry the data from one computer to the other. The access method used by the computers to put data on the communication medium is called token passing. Unlike the bus topology, the ring is an active topology. Each computer on the ring acts as a repeater to boost the signal and pass it to the next computer until it reaches the destination computer. The receiving computer strips the data from the token and returns the token to the sending computer with an acknowledgement. After verification, is regenerated andisrelease forone usecomputer, by any other computer requiring the datatoken transfer. While the token in use by other computers on the ring cannot transmit, because only the computer with the token can transmit data. This ensures that there are nom collisions and hence no times spend waiting for computers to resend data after a collision.

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All computers have equal access to data. During peak usage performance is even for all users. Ring networks perform well with heavy network traffic.

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Each computer acts as a repeater and as a result there is little signal degradation. Disadvantages  

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Network expansion or reconfiguration will disrupt network operations. If one computer fails, the whole network goes down.

Mesh Topology Apart from the three primary topologies, we also have the mesh topology. The mesh topology connects each computer to every other computer on the network (each computer has a point-to-point connection to every other computer on the network). Meshes use a significantly larger amount of network cabling than the other network topologies, which makes it more expensive. Every computer has multiple possible connection paths to the other computers on the network for redundancy. As a result, a single cable break will not stop network communications between any two computers computers..

The total number of connections required can be calculated using the following formula: Number of connections = n*(n-1)/2 Where n is the number of stations.

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Exercise 1. Illustrate the following topologies i) Star ii) Ring iii) Bus iv) Mesh  

 

 

 

 

[2marks each]

2. A computer network has a number of disadvantages. These include; rapid spreading of viruses when any machine is infected, potential loss of privacy, data corruption and destruction by other uses amongst other. Explain why managers implement computer networks [8marks]  

3. Explain the following terms as used in computer networks and data communications. i) Signal multiplexing ii) Circuit switching [4marks]  

 

 

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3.11 Ethical Challenges of Computing Ethics, in the classical sense, refers to the rules and standards governing the conduct of an individual with others. As technology and computers became more and more a part of our everyday lives, we must understand that the problems that have always plagued business business and conduct conduct will continue to be a problem. problem. In fact, a new medium can provide provide even more diffic difficult ult questions of judgment. judgment. In other words, since the introduction of the World Wide Web, the definition of ethics has evolved, too. A new type of ethics known as computer ethics has emerged. Computer ethics is concerned with standards of conduct as they pertain to computers. Overall, this seems rather a lightweight introduction to a subject crawling with deep complexities, but since I was recently asked by a student for  just such a publication, it may be one whose time time has come. come. Six major issues in Computer Ethics (1) Unauthorized and illegal database entry, surveillance and monitoring, and privacy issues; (2) Piracy and intellectual property theft; (3) Equity and equal access; (4) Philosophical implications of artificial intelligence and computer rights; (5) Social consequences of robotics and the automated office, human skill obsolescence, obsolescenc e, and job displacement; (6) Computers as tools of war. Formulating rules & regulations for computer use in an organization Rules on Computer Usage  

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You must Use only the computers, computer accounts and computer files for which you have authorization. Do not use another individual's ID or account, or attempt to capture or guess other users' passwords. Users are individually responsible for all use of resources assigned to them; therefore, sharing of accounts is prohibited. Respect the privacy and personal rights of others. Do not access or copy another user's e-mail, data, programs, or other files without permission. Always ensure that your connected computer has most up-to-date OS and software patches.

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Always ensure that your connected computer has properly configured and up-to-date antivirus software and you regularly scan your computer for viruses. Use UM computing facilities with utmost cares. You must must not not Alter IP address address without without authorized permission; Changing IP address may cause IP conflict or breach network security. Attempt to access restricted portions of the operating system (e.g. registry) or security software (e.g. Active Directory) unless authorized by the appropriate PTj’s representative (Wakil ICT). Don’t use computer not assign to you, other than those designated as public machines, without the consent of the owner or the system's administrator. Don’t commit computer vandalism, which is defined as any malicious attempt to harm or destroy hardware, software or data of another computer through the network. This includes but not limited to the dissemination of viruses. Obtain access to services and data that do not belong to you, in other words, don’t use the Campus Network to gain unauthorized unauthorized access to any computer systems. Alter or destroy data that does not belong to you. Use campus computing resources to attack computers, accounts, or other users by launching viruses, worms, trojan horses, or other attacks on computers here or elsewhere. Perform unauthorized vulnerability scans on systems; such scanning is considered to be a hostile act. Use campus computing resources to harass or threaten others. Knowingly or carelessly performing acts which will interfere with the normal operation of computers, terminals, peripherals, or networks Knowingly or carelessly running or installing on any computer system or network, or giving to another user, a program intended to damage or to place excessive load on a computer system or network. Create, install, or knowingly distribute computer virus, "Trojan horse", or other surreptitiously destructive program on any University computer or network regardlessdata of whether any demonstrable results. Attempt facility, to circumvent protection schemes orharm uncover security loopholes. This includes creating and/or running programs that are designed to identify security loopholes and/or decrypt intentionally secure data. Move large files across networks (excluding official tasks) such that it degrades resource performance. Post electronic bulletin boards materials that violate existing laws. Endanger or interfere with the operation of any computer system by any means. Send electronic messages to unwilling recipients. Transmit or post fraudulent, defamatory, harassing, obscene, or threatening messages, or any communications prohibited by law.

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Executing any form of network monitoring which will intercept data not intended for his/her host unless this activity is a part of the his/her normal  job/duty.

Data Privacy & Protection Information privacy, or data privacy: Is the relationship between collection and dissemination of data,  data,  technology,  technology,  the public expectation public  expectation of privacy, and privacy, and the legal the legal and political and political issues surrounding them. Privacy concerns exist wherever personally identifiable information is collected and stored - in digital form or otherwise. Improper or non-existent disclosure control can be the root cause for privacy issues. Data privacy issues can arise in response to information from a wide range of sources. Data protection Data security is the means of ensuring that data is kept safe from corruption and that access to it is suitably controlled. Thus data security helps to ensure ensure privacy.  privacy. It  It also helps in protecting personal data. Data Security Technologies Disk Encryption Disk encryption refers to encryption technology that encrypts data on a hard disk drive.   Disk encryption typically takes form in either software (see disk encryption drive. software]] or hardware (see disk encryption hardware). software hardware). Disk encryption is often referred to as on-the-fly encryption ("OTFE" ("OTFE")) or transparent encryption Hardware based Mechanisms for Protecting Data Software based security solutions encrypt the data to prevent data from being stolen. However, a malicious program or a hacker may corrupt the data in order to make it unrecoverable or unusable. Similarly, encrypted operating systems can be corrupted by a malicious program or a hacker, making the system unusable. Hardware-based security solutions can prevent read and write access to data and hence offers very strong protection against tampering and unauthorized access. Hardware based or assisted computer security offers an alternative to software-only computer security. Security tokens such as those using PKCS#11 may be more secure due to the physical access required in order to be compromised. Access is enabled only when the token is connected and correct PIN is entered (see two

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factor authentication). However, dongles can be used by anyone who can gain physical access to it. Newer technologies in hardware based security solves this problem offering fool proof security for data. Working of Hardware based security: A hardware device allows a user to login, logout and to set different privilege levels by doing manual actions. The device uses biometric technology to prevent malicious users from logging in, logging out, and changing privilege levels. The current state of a user of the device is read by controllers in peripheral devices such as harddisks. Illegal access by a malicious user or a malicious program is interrupted based on the current state of a user by harddisk and DVD controllers making illegal access to data impossible. Hardware based access control is more secure than protection provided by the operating systems as operating systems are vulnerable to malicious attacks by viruses and hackers. The data on harddisks can be corrupted after a malicious access is obtained. With hardware based protection, software cannot manipulate the user privilege levels, it is impossible for a hacker or a malicious program to gain access to secure data protected by hardware or perform unauthorized privileged operations. The hardware protects the operating system image and file system privileges from being tampered. Therefore, a completely secure system can be created using a combination of hardware based security and secure system administration policies. Backups Backups are used to ensure data which is lost can be recovered Data Masking Data Masking of structured data is the process of obscuring (masking) specific data within a database table or cell to ensure that data security is maintained and sensitive customer information information is not leaked outside of the authorized environment. environment. Data Erasure Data erasure is a method of software-based overwriting overwriting that completely destroys all electronic data residing on a hard drive or other digital media to ensure that no sensitive data is leaked when an asset is retired or reused. International Laws and Standards International Laws In the UK, the UK, the  the Data  Data Protection Act is used to ensure that personal data is accessible to those whom it concerns, and provides redress to individuals if there are inaccuracies. This is particularly important to ensure individuals are treated fairly,

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for example for credit checking purposes. The Data Protection Act states that only individuals and companies with legitimate and lawful reasons can process personal information and cannot be shared. International Standards The International Standard ISO/IEC 17799 covers data security under the topic of information security, and security, and one of its cardinal principles is that all stored information, i.e. data, should be owned so that it is clear whose responsibility it is to protect and control access to that data. The  Trusted Computing Group is an organization that helps standardize computing The  security technologies. technologies. 1.4 Legal issues in software licensing Software license A software license is a legal instrument (by way of contract law) governing the usage or redistribution of software. All software is copyright protected, irrespective of whether it is in the public domain. Contractual confidentiality is another way of protecting software. A typical software license grants an end-user permission to use one or more copies of software in ways where such a use would otherwise constitute copyright infringement of the software owner's exclusive rights under copyright law. Some software comes with the license when purchased off the shelf or an OEM license when bundled with hardware. Software can also be in the form of freeware or shareware. Software shareware. Software licenses can generally be fit into the following categories: proprietary licenses and free and free and open source licenses, which include free software licenses and other open source licenses. The licenses. The features that distinguishes them are significant in terms of the effect they have on the end-user's rights. A free or open source license makes software free for inspection of its code, modification of its code, and distribution. While the software released such a license, like the GNU the GNU General Public License can be sold for money, the distribution cannot be restricted in the same ways as software with copyright and patent restrictions used by firms to require licensing fees. Proprietary software The hallmark of proprietary software licenses is that the software publisher grants a license to use one or more copies of software, but that ownership of those copies remains with the software publisher (hence use of the term "proprietary"). "proprietary"). One consequence of this feature of proprietary software licenses is that virtually all rights regarding the software are reserved by the software publisher. Only a very

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limited set of well-defined rights are conceded to the end-user. Therefore, it is typical of proprietary software license agreements to include many terms which specifically prohibit certain uses of the software, often including uses which would otherwise be allowed under copyright law. The most significant effect of this form of licensing is that, if ownership of the software remains with the software publisher, then the end-user must must   accept the software license. In other words, without acceptance of the license, the end-user may not use the software at all. One example of such a proprietary software license is the license for Microsoft Windows.   As is usually the case with proprietary software licenses, this license Windows. contains an extensive list of activities which are restricted, such as: reverse engineering, simultaneous engineering,  simultaneous use of the software by multiple users, and publication of benchmarks or performance tests. Free and open source software With a free software license, in license, in contrast to proprietary software licenses, ownership of a particular copy of the software does not remain with the software publisher. Instead, ownership of the copy is transferred to the end-user. As a result, the enduser is, by default, afforded all rights granted by copyright law to the copy owner. Note that "copy owner" is not the same as "copyright owner". While ownership in a particular copy is transferred, ownership of the copyright remains with the software publisher. Additionally, a free software license typically grants to the end-user extra rights, which would otherwise be reserved by the software publisher. With a free software license, in contrast to proprietary software licenses, a primary consequence of the free software form of licensing is that acceptance of the license is essentially optional -- the end-user may use the software without accepting the license. However, if the end-user wishes to exercise any of the additional rights granted by a free software license (such as the right to redistribute the software), then the end-user must accept, and be bound by, the software license. Open source licenses generally fall under two categories: Those that aim to preserve the freedom and openness of the software itself ('copyleft' licenses), and those that aim to give freedom to the users of that software (permissive license licenses). s). An example of a copyleft Free Software license is the GNU General Public License (GPL). This license is aimed at giving the end-user significant permission, such as permission to redistribute, reverse engineer, or otherwise modify the software. These permissions are not entirely free of obligations for the end-user, however. The end-user must comply with certain terms if the end-user wishes to exercise these extra permissions granted by the GPL. For instance, any modifications made and redistributed by the end-user must include the source code for these, and the

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end-user is not allowed to re-assert the removed copyright restrictions back over their derivative work. Examples of permissive free software licenses are the BSD license and the MIT license, which license,  which essentially grant the end-user permission to do anything they wish with the source code in question, including the right to take the code and use it as part of closed-source software or software released under a proprietary software license. Other characteristics characteristics In addition to granting rights and imposing restrictions on the use of software, software licenses typically contain provisions which allocate liability and responsibility between the parties entering into the license agreement. In enterprise and commercial software transactions these terms (such as limitations of liability, warranties and warranty disclaimers, and indemnity if the software infringes intellectual property rights of others) are often negotiated by attorneys specialized in software licensing. The legal field has seen the growth of this specialized practice area due to unique legal issues with software licenses, and the desire of software companies to protect assets which, if licensed improperly, could diminish their value. Software licenses and copyright law In the United States, Section 117 of the Copyright Act gives the owner of a particular copy of software the explicit right to use the software with a computer, even if use of the software with a computer requires the making of incidental copies or adaptations (acts which could otherwise potentially constitute copyright infringement). Therefore, the owner of a copy of computer software is legally entitled to use that copy of software. Hence, if the end-user of software is the owner of the respective copy, then the end-user may legally use the software without a license from the software publisher. As many proprietary "licenses" only enumerate the rights that the user already has under U.S.C 17, S 117, and yet proclaim to take rights away from the user, these contracts may lack  lack  consideration. consideration. Proprietary  Proprietary software licenses often to proclaim to give software publishers more control over the way their software is used by keeping ownership of each copy of software with the software publisher. By doing so, Section 117 does not apply to the end-user and the software publisher may then compel the end-user to accept all of the terms of the license agreement, many of which may be more restrictive than copyright law alone. It should be noticed that the form of the relationship determines if it is a lease or a purchase,

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3.12 Applications (word processing)- Ms Word Microsoft Word 2003/2002 for Windows This tutorial teaches Microsoft Word basics. Although knowledge of how to navigate in a Windows environment is helpful, this tutorial was created for the computer novice. To begin, open Microsoft Word. Your screen will look like the one shown here.

Click the X in the upper right corner of the New Document pane to close the New Document pane. Your screen will then look like the one shown here.

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The Title Bar

This lesson will familiarize you with the Microsoft Word screen. We will start with the Title bar, which is located at the very top of the screen. On the Title bar, Microsoft Word displays the name of the document on which you are currently working. At the top of your screen, you should see "Microsoft Word - Document1" or a similar name. The Menu Bar

The Menu bar is generally found directly below the Title bar. The Menu bar displays the menu. The Menu bar begins with the word File and continues with Edit, View, Insert, Format, Tools, Table, Window, and Help. You use the menus to give instructions to the software. Point with your mouse to a menu option and click the left mouse button to open a drop-down menu. You can now use the left and right arrow keys on your keyboard to move left and right across the Menu bar options. You can use the up and down arrow keys to move up and down the drop-down menu.

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The most frequently used menu options appear on the menu list. A chevron appears at the bottom of the list. Click the chevron to display additional menu options.

To select an option, click the option or use the arrow keys to move to the option on the drop-down menu and press Enter. An ellipse or a right arrow after a menu item signifies additional options; if you select that menu item, a dialog box appears. Items in gray are not available. You can customize your screen so that all of the menu options display when you click a menu item. This tutorial assumes that your menu is set to display all menu options. To customize your menu to display all of the menu options: 1. Click Tools on the Menu bar. 2. Click Customize on the drop down menu. The Customize dialog box opens. 3. Click the Options tab.  

 

 

 

4. Click in the check box to select Always Show Full Menus.

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Exercise 1  1  Do the following exercise. It demonstrates using the Microsoft Word menu. 1. Click File on the Menu bar. 2. Press the right arrow key until Help is highlighted.  

 

 

3. 4. 5. 6. 7.

 

     

Press the left arrow key until Format is highlighted. Press the down arrow key until Styles and Formatting are highlighted. Press the up arrow key until Paragraph is highlighted. Press Enter to select the Paragraph menu option. Click Cancel to close the dialog box.

Toolbars

The Standard Toolbar

The Formatting Toolbar Toolbars provide shortcuts to menu commands. Toolbars are generally located just below the Menu bar. Before proceeding with this lesson, make sure the toolbars you will use -- Standard and Formatting -- are available. Follow these steps: 1. Click View on the Menu bar. 2. Highlight Toolbars. 3. Standard and Formatting should have check marks next to them. If both Standard and Formatting have heck marks next to them, press Esc three times to close the menu. 4. If they do not both have check marks, click Customize. 5. Click the Toolbars tab. 6. Point to the box next to the unchecked option and click the left mouse button to make a check mark appear. Note: You turn the check mark on and off by clicking the left mouse button. 7. Click Close to close the dialog box.  

 

 

 

 

 

 

The Ruler

The ruler is generally found below the main toolbars. The ruler is used to change the format of your document quickly. To display the ruler: 1. Click View on the Menu bar.  

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2. The option Ruler should have a check mark next to it. If it has a check mark next to it, press Esc to close the menu. If it does not  have  have a check mark next to it, continue to the next step. 3. Click Ruler. The ruler now appears below the toolbars.  

 

Document View In Word, you can display your document in one of five views: Normal, Web Layout, Print Layout, Reading Layout, or Online Layout. Normal View   Normal view is the most often used and shows formatting such as line spacing, font, point size, and italics. Word displays multiple-column text in one continuous column. Web Layout   Web layout view enables you to view your document as it would appear in a browser such as Internet I nternet Explorer. Print Layout   The Print Layout view shows the document as it will look when it is printed. Reading Layout   Reading Layout view formats your screen to make reading your document more comfortable. Outline view  view  Outline view displays the document in outline form. Headings can be displayed without the text. If you move a heading, the accompanying text moves with it. Tables Working With Tables  Tables  Now that we've covered how to insert tables and how to navigate within them, let's cover some of the other issues that arise while working with tables. The last issue covered the options of evenly distributing rows or columns.

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So... moving on, what about the situations where you want the columns different widths? Is there an easy way to accomplish this effect? You bet!  Adjusting  Adjusti ng the width of a column column   can be done by running your mouse pointer over the vertical lines dividing the columns. When the pointer switches switches to a doublesided arrow click and hold. Now you can drag the side of the column left or right, creating whatever width you need.

Row height  can  can also be adjusted in the same manner, using the divider line below the row. It is also a lso important to mention that row height will automatically be increased when text wraps within a cell. (Provided that you have not set the height using an exact measurement under the Table Table menu,  menu, Cell Height and Height and Width Width choice.)  choice.) Something that automatically expands expands to fit … hmm… ever wish your clothes would do that? Another way to set row height and column width is to click the Table Table   menu, Cell Height and Width choice. Width choice. In the resulting window you will have a row or column tab at the top to choose from. Keep in mind, changes set there will affect only the row or column your cursor is currently in.

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To change settings for multiple rows or columns, highlight all cells that need to be changed and go through the menu to set the changes. If only that worked in real life, highlight all rooms, vacuum one and they're all vacuumed…in my dreams!  dreams!  Within the cell of a table, the normal font formatting (font size, type, bold, italic, underline, etc…) and alignments (left, center, right and justify) can be completed using the ususal methods. In addition, you can choose where to place the text within a cell of the table - known as Alignmen as  Alignment  t . You can align text to the top of the cell, the bottom or to the center. This option is extremely helpful with column headings. The following buttons can set the alignment.

Other ways to access alignment options would include the Table  Table  menu, Cell Height and Width  Width  (look at the bottom of the row tab) or right clicking clicking   on selected cells and choosing Alignment Alignment from  from the pop up menu. Once again, these changes will affect only the cell you are currently in or the cells highlighted at the time the changes are set.

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Along the same lines as the text alignment there is the changing of the text direction.   direction. This option allows you to set text to read up or down.

You can access this option in several ways. One of them is the Change Text Direction button on button on the Tables and Borders toolbar.  toolbar. 

Each click of the button will cycle through the possible changes for the text, finally returning you to the original left to right text. Another way would be to right click in click in the cell to be changed and use the Change Text Direction option Direction option on the resulting pop up menu. You can also sort also sort data data within a table. The fastest way would be to click in a cell and cell and then choose one of the sorting buttons on buttons  on the Tables and Borders toolbar.  toolbar. 

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These buttons will sort either ascending or descending, depending on the button you chose. All data in each row is kept together as a row and moved at the same time.  I would like to note that this method works best when you have only one  sort criteria. criteria. If you have multip multiple le criteria, located in separate separate columns, (such as by date and then by name) then you should use the next method.  method.   The other option for sorting is in the Table Table menu,  menu, Sort Sort choice.  choice.

A screen will open allowing you to choose your sorting options including the option to set sorting criteria using multiple columns. You can tell Word to sort first on one column and then for matching entries use a secondary column to determine order. OK, so for today that was changing column width, row height, alignment, text direction and data sorting. Whew! I'm tired after all that, how about you? Importing objects How to Insert Excel Data into Word Step 1:  1:  Open the Excel spreadsheet that contains your data, or create a new spreadsheet and enter your information. In this example, we’ll use the same monthly budget information information that we worked with in Part 4 of this series. Step 2: Select 2: Select all of the cells in your Excel spreadsheet that you want to insert into your Word document, and press Ctrl + C to C to copy the entire selection.

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Step 3: Switch over to your Microsoft Word document and place the cursor at the point in the document where you want to insert the data. Open the Home Home tab  tab on the Word ribbon, and click on the arrow underneath Paste Paste.. Select the Paste Special option. Special  option.

Step 4: In the Paste Special  Special  dialog box, choose the paste as Microsoft Office Excel Worksheet Object option.

If you later decide that you want to make any changes to this information, you don’t have to go through these steps again. You can edit the Excel spreadsheet directly within Microsoft Word simply by double-clicking double-clicking on the object. You’re not restricted to just formatting edits either – you can make any changes to the table, including adding formulas and calculations, that you normally would make in Excel.

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Tip:  If you haven’t entered your data into Excel yet, you can bypass opening Excel Tip:  altogether by choosing Excel Spreadsheet  Spreadsheet  from the Table Table   dropdown list on the Insert   tab of the Word ribbon. This will open a blank Excel spreadsheet directly Insert inside your Word document in which you’ll have access to all of the functionality you normally would have within a regular Excel file. Using Tables and Charts in Microsoft Word 2007 In this series, we’ll take a look at how charts and tables can be used in Microsoft Word 2007 documents to help illustrate important concepts and keep the reader’s attention. Mail Merge

You use mail merge when you want to create a set of documents, such as a form letter that is sent to many customers. Each letter has the same kind of information, yet the content is unique. For example, in letters to your customers, each letter can be personalized to address each customer by name. The unique information in each letter comes from entries in a data source. The mail merge process entails the following overall steps: 1.

 

Set up the main document.  document.  The main document contains the text and graphics that are the same for each version of the merged document —  for example, the return address or salutation in a form letter.

2.

 

Connect the document to a data source.  source.   A data source is a file that contains the information to be merged into a document. For example, the names and addresses of the recipients of a letter.

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3.

Refine the list of recipients or items.  items.  Microsoft Office Word generates a

 

copy of the main document for each item, or record, in your data file. If your data file is a mailing list, these items are probably recipients of your mailing. If you want to generate copies for only certain items in your data file, you can choose which items (records) to include. 4.

Add placeholders, called mail merge fields, to the document.  document.  When you

 

perform the mail merge, the mail merge fields are filled with information from your data file. 5.

Preview and complete the merge.  merge.  You can preview each copy of the

 

document before you print the whole set. You use commands on the Mailings Mailings tab  tab to perform a mail merge. IMPORTANT

If you plan to use custom contact fields with the Contacts list in

Microsoft Office Outlook, you must begin must begin the mail merge process in Outlook.  Outlook.  TIP

You can also perform a mail merge by using the Mail Merge  Merge  task pane,

which leads you step by step through the process. To use the task pane, in the Start Mail Merge  Merge  group on the Mailings Mailings   tab, click Start Mail Merge, Merge, and then click Step by Step Mail Merge Wizard. Wizard. 

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Set up the main document 1.

 

Start Word.

A blank document opens by default. Leave it open. If you close it, the commands command s in the next step are not available. 2.

 

On the Mailings Mailings   tab, in the Start Mail Merge  Merge  group, click Start Mail Merge.. Merge

3.

 

Click Letters Letters..

You can also use mail merge to create: A catalog or directory  directory   The same kind of information, such as name and description, is shown for each item, but the name and description in each item is unique. Click Directory Directory to  to create this type of document. A set of envelopes  envelopes   The retu return rn address address is the same same on all the envelopes, but the destination address is unique on each one. For more information, see Create and print envelopes for a mass mailing.  mailing.  A set of mailing labels Each labels  Each label shows a person's name and address, but the name and address on each label is unique. For more information, see Create and print labels for a mass mailing.  mailing.  A set of e-mail messages  messages  The basic content is the same in all the messages, but each message goes to the individual recipient and each message contains information that is specific to that recipient, such as the recipient's

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name or some other piece of information. For more information, see Use mail merge to send personalized e-mail messages to your e-mail address list.  list.   Resume a mail merge If you need to stop working on a mail merge, you can save the main document and resume the merge later. Microsoft Office Word retains the data source and field information. If you were using the Mail Merge  Merge  task pane, Word returns to your place in the task pane when you resume the merge. 1.

 

When you're ready to resume the merge, open the document. Word displays a message that asks you to confirm whether you want to open the document, which will run a SQL command.

2.

 

Because this document is connected to a data source and you want to retrieve the data, click Yes Yes.. If you were opening a document that you did not realize was connected to a data source, you could click No No   to prevent potentially malicious access to data. The text of the document, along with any fields that you inserted, appears. appears.

3.

 

Click the Mailings Mailings tab,  tab, and resume your work.

Connect the document to a data source To merge information into your main document, you must connect the document to a data source, or a data file. If you don't already have a data file, you can create one during the mail merge process. If you use an existing list, make sure that it contains the information that you want to use, including all the columns and the rows. You can make some changes during

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the merge, but you can't open your data source separately during the merge. The merge process is easier if your data source is ready before you connect to it.

Choose a data file 1.

On the Mailings Mailings   tab, in the Start Mail Merge  Merge  group, click Select

 

Recipients.. Recipients

2.

Do one of the following:

 



 

Use Outlook Contacts  Contacts  If you want to use your your Contacts lis listt in Outlook, click Select from Outlook Contacts. Contacts . For more information about using the Contacts list, see Tips for working with Microsoft Office Outlook Contacts list.  list.  



 

Use an existing data source file  file   If you ha have ve a Microsoft Microsoft Office Excel worksheet, a Microsoft Office Access database, or another type of data file, click Use Existing List, List , and then locate the file in the Select Data Source dialog Source dialog box. For Excel, you can select data from any worksheet or named range within a workbook. For Access, you can select data from any table or query (query: A means of finding all the records stored in a data source that fit a set of criteria you name. Queries can contain operators, quotati quotation on marks, wildcard characters, and parentheses to help focus your search.) that is defined in the database.

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For tips on formatting the data in your Excel worksheet for mail merge, see Tips see  Tips for formatting data in Office Excel.  Excel.   For another type of data file, select the file in the Select Data Source  Source  dialog box. If the file is not listed, select the appropriate file type or select All Files  Files  in the Files of type  type  box. In a mail merge, you can use the following types of data files: Files from single-tier, file-based database programs for



 

which you have installed an OLE DB (OLE DB: A component database architecture that implements efficient network and internet access to many types of data sources, including relational data, mail files, flat files,

and

spreadsheets.)

provider

or

ODBC (Open

Database

Connectivity (ODBC): A standard method of sharing data between databases and programs. ODBC drivers use the standard Structured Query Language (SQL) to gain access to external data.) driver (a number of which are included with Microsoft Office). An HTML file that has a single table. The first row of the



 

table must contain column names, and the other rows must contain data. Electronic address books:



 

 



Microsoft Outlook Address Book



Microsoft Schedule+ 7.0 Contact List



Any similar address lists that were created with a

 

 

MAPI (MAPI: The Microsoft interface specificatio specification n that allows different messaging and workgroup applications (including e-mail, voice mail, and fax) to work through a single client.)-compatible client.) -compatible messaging system, such as Microsoft Outlook. 

 

A

Microsoft

Word

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The

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headings, and the other rows must contain the records that you want to merge. You can also use a header source (header source: A document that contains the header row (or header record) to be used with the data source specified for a mail-merge main document.) as a data source. Any text file that has data fields (data field: A category of information that corresponds to one column of information in a data source. The name of each data field is listed in the first row (header row) of the data source. "PostalCode" and "LastName" are examples of data field names.) separated (or delimited) by tab characters or commas and data records (data record: A complete set of related information that corresponds to one row of information in the data source. All information about one client in a client mailing list is an example of a data record.) separated by paragraph marks. Create a new data file in Word  Word  If you don't have a data file file



 

yet, click Type New List, List, and then use the form that opens to create your list. The list is saved as a database (.mdb) file that you can reuse. For more information, see Type see Type a new list.  list.  Advanced image editing Step 1. Open Microsoft Word. Remember to leave your browser window open until this lesson is finished.  finished.   Step 2. Open 2. Open a new blank document using keyboard commands    

IBM - Use Ctrl+N (Hold down the Ctrl key and tap the N key one time) Macintosh - Use Command+N (Hold down the Command key and tap the N key one time)

Step 3.  3.  Turn the document to landscape orientation, that makes the longest dimension the width of the page, not the depth. Go to the File File menu,  menu, select Page Page   Options, choose choose Orientation  Orientation and select Landscape. Landscape.   Step 4. Enter 4. Enter the following line at the top of the page: Classroom Computer Rules Compiled by ICT Department©2011

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 

Do not use all caps anywhere on the page. The eye has difficulty scanning text in an all caps format, even including headlines.

Step 5.  5.  Copy the following rules and paste them into your document two lines below the headline using toolbar buttons, menu items or keyboard combinations: Sign in before using any Internet connected computer. Save only to the Desktop or a floppy disk. Get the teacher's permission before printing. No food or drinks near the computers, no exceptions! If you don't know how to do something, ask. Click and drag to highlight the rules you see above. With the text selected use the toolbar button, menu item or keyboard combination to copy text. Go to the new Word document and paste what you copied using the toolbar button (it looks like a clipboard), menu item (it is in the Edit menu) or keyboard combination (IBM=Ctrl+V, Mac=Command+V). Step 6. Highlight 6. Highlight the title (Classroom Computer Rules) and perform the following actions using toolbar buttons, menu items or keyboard combinations:            

Format the text to Bold Increase the side to 36 pt. Center the text Click Bold button to remove Bold Return text size to default Note: all of these actions can be performed using the Formatting toolbar.

Step 6.  6.  Highlight the five rules and perform the following actions using toolbar buttons, menu items or keyboard combinations: combinations:    



 

Format the text to Bold Increase the side to 24 pt. Left align the text, if it is not already aligned

Note: all of these actions can be performed using using the Formatting toolbar. Step 7. Place 7. Place your cursor under the title, but above the five rules. You may have to hit Enter/Return to do this. In Word go to the Insert Insert   menu, select Picture Picture   then Clip Art.  Art.  Insert the image named computer training. It can be found in any of the following clip art libraries on Office: Academic, Office, People At Work, Computers, PCs, Computer Hardware, Students, Schools, Education, or Personal Computers.

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Step 8. With the picture selected, go to the Format Format   menu and select Format Format   Picture.. There are several things that you can do with this picture. Picture Tab   Tab

Actions available  available     

Picture   Picture  

 

 

Wrapping   Wrapping

 

 

Colors Lines   Lines

and

 

Five styles of wrapping allow you to place an image in the middle of a block of text Four possible alignment of text choices are offered distance from the text to the picture can also be specified Place a block of color or a pattern behind the image Place a box around the image, change the thickness and character of the line making the box

 

Change the size of the picture using an inches scale, or a percent scale (best done by clicking and dragging)

 

Change the position of the image on the page (best done by clicking and dragging)

Size   Size

Position   Position

Crop the picture one margin at a time t ime Change the color to grayscale, black and white, or make a very light watermark out of the image Change the brightness or contrast of the image

Step 9. Resize the image by clicking and dragging.  dragging.   Click once on the image and it will be surrounded by eight boxes; one at each corner, and one in the middle of each line. Compiled by ICT Department©2011

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If you click on a box in the middle of a line and drag outward from the center of the image you will change only the width or height of the picture, causing distortion. If you click on a corner box, hold the shift key down, and drag outward from the picture you will change width and height proportionally. If the aspect ratio is locked, Word automatically does this without your having to hold down the shift key. Step 10. Move the image by clicking and dragging. Click once on the image and it will be surrounded by eight boxes; one at each corner, and one in the middle of each line. Move your cursor over the image and it becomes a pointer with a four headed arrow attached to it. Click anywhere in the picture and drag it to the desired location. Assignment   Assignment Leave your browser window open. Open Microsoft Word, if it is not already open.   open. 1. Open a new Word document to be used to create a certificate. This certificate will be awarded by a student to his/her favorite character in a book 2. Turn the document to Landscape orientation. 3. Insert an image at the top center of the page using Word Clip Art. 4. Create a title for the certificate. Suggestion: "My Favorite Character" 5. Insert a name. Suggestion: "Character's name from book". 6. Write a short statement as to why the character was chosen. 7. Draw a line and leave a place for the student's name to be signed. 8. "Student's Name" below the line. 9. Print Save the document. document.    One possible use of this certificate would be as a template for students to use to give you a novel book report.  report.  

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3.13 Spreadsheet-Ms Excel Starting Excel 2003 In the following exercises you will learn learn   some of the necessary steps to create create   a spreadsheet using spreadsheet  using Microsoft Excel 2003 for 2003 for Windows 2000, Me, and XP. You will learn not only how to type various items into the spreadsheet, but also how to copy columns, widen columns, fill columns, add, subtract, multiply, divide, do graphics and a variety of other ―things.‖  

To begin, load load   the spreadsheet by quickly quickly   clicking twice  twice  on the Excel 2003 Windows Icon  Icon  in the Windows Screen. Screen. If you do not see an see an Excel Icon, Icon, click click-on -on the Start Button in Button in the lower left corner   of the screen, move the cursor up to Programs corner Programs,, and then move to Microsoft Excel 2003 and click click-on -on it.

A spreadsheet spreadsheet   is a ―number ―number manipulator.‖ manipulator.‖ To make the manipulation of numbers easier all spreadsheets  spreadsheets  are organized into rows rows   and columns columns.. Your initial spreadsheet will look something like the one below:

Notice that the ―main Notice  ―main‖‖ part of the spreadsheet is composed of Rows (Labeled 1, 2, 3, 4, 4, etc.) and Columns (Labeled A, B, C, D, D , etc.). etc.). There are are a lot of rows rows and columns in a spreadsheet. spreadsheet .

The ―intersection intersection‖‖ of each row  row  and column column   is

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called a cell cell.. In the the image image above above the the cursor is on  on the ―home ―home‖‖ cell cell  – A1 A1.. Notice Row 1 and Column Column A are “bold,” and and  colored “orange.” This indicates what  what is “orange.” This indicates cell.. Notice   right above cell  Notice cell  A1 A1,, that A1 A1   is called the ―address ―address   of the cell displayed in displayed  in a small box called box called the Name Box. Box. Whenever you ―click‖ on a cell the address of that cell will be shown in the Name Box. You can move around the spreadsheet/cells by clicking clicking   your mouse on on   various cells,, or by using the up, down, right and left arrow movement keys on the cells keyboard.. Or, you can move up and down by using the ―elevator keyboard ―elevator‖‖ bars on the right   and bottom right bottom   of the spreadsheet. spreadsheet . Go ahead and move around the spreadsheet.. Hold down  spreadsheet down  the down arrow key  key  on the keyboard keyboard   for a few seconds –  then click click-on -on a cell cell.. Notice Notice   how the Name Box  Box  always tells tells   you  ―where  ―where you are.‖ are.‖ Now hold down the right arrow key on key on the keyboard for a few seconds. Notice Notice how  how the alphabet changes from changes from single letters (A, B, C,. …. Z) Z) to several letter combinations (AA, AB, AC). AC ). There are hundreds of columns  columns  and thousands of rows  rows  in a spreadsheet. Anytime Anytime you  you desire to return return to  to the Home Cell (A1)  (A1)  simply click-in click-in   the Name Box  Box  and type-in A1. A1. Then tap tap   the Enter key  key  and you will go go   to cell A1 A1.. You can go to any cell by this method. Simply type-in type-in a row and column, tap the Enter key, and you’ll go to that cell.  

Now that you have the ―feel‖  of   of how to move around Excel spreadsheet, spreadsheet, go to the to the cells as cells  as indicated below  below  and type-in type-in the  the following:

Cl  Cl 

(Your Name)'s Budget. It should look similar to similar to the image below. below. Do not tap Enter when Enter when you finish

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Look at cells C1 Look at C1 and  and D1 D1.. Notice how your entry has spilled over from C1 into D1.. Sometimes this is a problem, and sometimes it is not. Tap D1 Tap the  the Enter key and key and then click click-on -on cell D1 D1 and  and type-in type-in the  the word BONZO and tap tap  Enter key key..

Notice  how Bonzo Notice  Bonzo   now COVERS COVERS   the right part of your original entry!! entry!! Now move back to back to cell C1 C1 and  and click-on it. it. Look at the upper part of the spreadsheet, spreadsheet,  just above the cells where you typed Bonzo. Your name and the word budget are still there! Bonzo only COVERED COVERED   the portion in cell D1. D1. See the image and arrow below.

There are several ways to ways to take care  care of this. For the moment move back to back to cell D1 and D1  and click click-on -on cell D1 D1.. Tap Tap the  the Delete key (above the arrow movement keys on the keyboard keyboard). ).

Notice that Bonzo Bonzo   disappears disappears   and your entire entry

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reappears. This is one way to expose the entry. We'll look at some others as we reappears. go along. Now we'll continue making some entries. Move Move to  to the following cells  cells  and type-in type-in the  the information indicated. indicated. You can click-on each cell and then typein the entries. If you happen to make a mistake  mistake  simply retype the entries. entries. Later on we'll see see how to edit mistakes. mistakes. Any time you want want to replace something something in a cell you can simply retype a new entry and it will replace the old one. Cell

A10

Type-in  Type-in 

A3

Income

B4

Parents

B5

Job

B6

Investments

B7

Total

Expenses

B11

Food

B12

Beverages

B13

Parties

B14 Miscellaneou s B15

Total

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Your spreadsheet spreadsheet should  should now look like the picture picture on  on the right right..

At this point you probably have noticed, the words "Investments" and "Miscellaneous" run over the spaces given in the cells. Do not be concerned at this point. We’ll soon fix this.

Now, type the numbers numbers   in the cells indicated:

C4

300 C5

50

C6

150

When you type type-in -in the 150 150,, tap Enter.. Enter

Your spreadsheet spreadsheet   should look like   the one on the right like right.. We would like to place an underline at underline at the bottom of the three that we can indicate indicate   a total below  below  –  in cell C7 C7.. Point to cell mouse. we want the line -- always move theon the place That's wherewhere you want to insert a line. line . With the Arrow tap the RIGHT mouse button. button.

A sub-menu appears.. appears

with

a caption Format

Cells

figures  figures  so C7   with the C7 cursor to  cell C7 C7 

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The right click  click  will ―always ―always bring up‖ up‖ a menu menu   that is ―tailored ―tailored‖‖ to the ―place ―place‖‖ where you click. click. This will work in any Microsoft Windows Windows product. product. You can always tell “where” you click the right mouse  mouse   button for the cursor arrow will always be in a corner of the menu that appears – exactly where you clicked the right mouse button..

Select Format Cells.

When the Format Cells menu screen below appears, select appears, select Border Border..

Look at the Line Style  Style  box in the lower right. right. There are several types of lines that you can choose. Point to the thick single line in line in the Style Area (see arrow) and click click   the left   mouse button. A left box will box  will go around the line.. Look at the area line which says Border. Point to the upper part of the Text box (see arrow) and click click   the left   mouse button. A left thick black line will appear at the top top of  of the Text Text box.  box.

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If the thick line  line  does not show-up at the top of top  of the Text box, box, click-again click-again   at the ―top line area in the Text box‖ and the line will ―disappear‖. Then click-on click -on the thick, single line in the Line Style box again and repeat the previous instructions. If, somehow, you make a mistake mistake,, simply click click   ―  ―on on and off in the Text line boxes.‖‖ You will notice that the lines appear and disappear. This is called a boxes.  ―toggle‖ in computer jargon. So, work at this until you get the line on the top or where you want it. We have just indicated th that at we want a single thick un underline derline at the top of the cell C7. Point to OK and click click the  the left left mouse  mouse button. When you return return   to the spreadsheet, spreadsheet,   click somewhere other than cell C7. C7. away.‖ You should now see see   a line line   at the top top of  of cell C7 C7.. This is called ―clicking ―clicking away.‖ Sometimes the box highlighting a cell hides the lines. If you ―messed―messed -up‖, try again. Now type in the numbers in the cells indicated.

C11

30

C12

50

C13

150

C14

70

(After you you type  type 70, tap the the Enter  Enter key)

Now, underline the the top  top of  cell C15 C15 like  like you did cell C7 C7.. Widening Columns You probably noticed noticed,, as you typed in the numbers, some some of  of the words words were  were just too wide for wide for the default cell width  width (Investments and Miscellaneous). Miscellane ous). Let's widen column B to B to take care of this. Slowly move the move the mouse arrow to arrow to the right edge of edge of the B cell (between (between the B and the C). C). The cursor cursor will turn into into an arrow pointing right and left with a small vertical line in the middle (see arrow below).  below).   Hold down  down  the left mouse button and button and move (drag) the line to the right.

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As soon as you start to move (drag),  (drag),  a dotted vertical line will line will go down the spreadsheet and spreadsheet  and it will move as you hold down the left button and drag the mouse.. Keep dragging to mouse dragging to the right until until you  you are past past the  the widest word and word and a bit more (for Releasebelow the button. Themenu column is and widened. in the upper left some cornerspace). of the screen, File in the bar, above Notice the buttons, that as you hold down and drag that it tells you that current width of the column.

This is one way to widen a column. column. Here is another way. way. Point to the B at the top of column  column  B (in the Gray Gray area)  area) and click click the  the left   mouse button (The cell left cell   should turn dark blue  blue  and the column light column  light  blue blue.). .).

Now, keeping keeping   the cursor cursor   somewhere in the ―blue ―blue‖‖ area, click click   the Right Mouse Button. Button. Notice that a menu   with menu appears. Column Width…  Width…  Click-on Click -on Column Width…  Width…  and type type   in 15 and click-on click -on OK OK.. column.

Inserting Rows

This is another way to

widen

a

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Oops... a mistake Oops... mistake  (on purpose). We haven't left enough room at room at the top of the spreadsheet to insert some insert some budget months months.. So... move the cursor to the gray 2  2  along the left left   edge (this is the second row) so we can insert two new rows. Click   the left Click left   mouse button. You will notice that the whole row goes light blue  blue  and the 2 turn‟s turn‟s dark blue. Make sure the sure the cursor arrow arrow is  is either on the 2 or 2 or somewhere in the blue row. row .

Click  the RIGHT Click  RIGHT   mouse button. A drop down menu will appear. Point to Insert. Click  Click  the left button on on   Insert. Insert. Notice   how one row  Notice row  was inserted inserted   and how everything below   moved down. below down. Do this again again   to insert another row.. Excel, and all spreadsheets, row spreadsheets , will remember where they moved your work and automatically adjust for these changes. Income Income should  should now now be  be in cell A5. A5. Aligning Cells

Now we'll type some more. Go to cell

C3

SEPT (Type-in SEPT and and tap  tap the the Enter  Enter key key) ) 

Notice again how SEPT SEPT is  is automatically left aligned. aligned. Logically, since you are using Excel, the English version, the text is left aligned so that all of the text entries will line up nicely in the column cells. We would like to center SEPT in SEPT in cell C3. C3. Click on cell C3 C3   to ―mark mark‖‖ the cell. One way to center SEPT  SEPT  is to simply click-on click-on   the Center button in button in the button bar at bar at the top of the screen. screen . Make sure that sure that you

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are ON cell C3,  C3,  then clickclick-on on the  the  center button  button  (see image above  above  right right). ). You’ll notice that SEPT is now centered in cell C#.  C#. 

Here is another way to center center SEPT.  SEPT. Click RIGHT  RIGHT  on cell C3 C3.. Then click on Format Cells.

When the  Format the  Cells Menu appears, click-on

the   the

– 

Alignment Tab and then  then  click-on -- Horizontal Center --Vertical Center -- then click OK OK.. Try it.

This is how you can align words for neatness. You can also point to several cells you want aligned and do this. We'll try that next. next.

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Now type the below text in the cells indicated.

D3

OCT

E3

NOV

F3

DEC

G3 MONTHLY TOTALS  TOTALS  width of width  of

(tap tap   the Enter Enter   key and then correct the

this column)

Next we‟ll highlight cells highlight cells C3 through G3. G3. To do do this, point to C3 and click the Left mouse button. button. Then, holding down the down the left mouse button, drag the mouse to the right through G3 – when the cells are highlighted – take your finger off of the left mouse button. button. Then point point   to the group group   of cells and cells and click the right mouse button to bring up the Format Cells menu. Click on Alignment and choose Center (vertical & horizontal). horizontal). Then point to  to  OK  OK  and click click   the left left   mouse button. All of the cells will then be as centered.

You could also also  click click the  the Center button as button as you did before.

MONTHLY TOTALS will TOTALS will not fit its space  space when you do this. But, you know what to do. do. Move the cursor over the line betwee between n cells G and H and drag the line to the right to widen the G cell just like you did a few minutes ago.

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Saving Spreadsheets  Spreadsheets 

We have done quite a bit of work so now is a good time time to save our our spreadsheet. spreadsheet. Point to File in the Menu Bar  Bar  at the top top   of the spreadsheet.. Point to Save As and click spreadsheet click-on Save As. As. A Save As menu box appears  appears  

(like like the  the one below below). ).

Notice in the upper left corner  corner  right   that there is a ―box ―box‖‖ to the right of Save In: with In: with a down pointing  pointing  arrow   to the right arrow right.. Click-on Click-on   the arrow.. This will show arrow show you  you all all   of the ―drives ―drives‖‖ and ―folders ―folders‖‖ where you may save your work. work.

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When you see the drop-down list in the Save in: area, choose the drive where you want to save your file. If you are going to use a diskette, put a formatted 3 ½ diskette in the A Drive,  Drive,   then click click-on -on the 3 ½ Floppy (A):.  (A):.  We are going to save our file on the Local Disk (C:) – our hard drive, so we chose that drive in the image above (see top arrow). arrow).

To the right of File name:, delete name:, delete the information (which is in the box) and typein MYBUDGET (see lower left arrow). arrow). This is the name name under which you you are saving your file. (In the future you will choose logical names for your spreadsheets as you save them.) Now point to Save and click click the  the left left mouse  mouse button (see lower right arrow). arrow).  

Exiting Spreadsheets

Anytime you need to leave your spreadsheet simply click on File File   in the menu bar, bar, then

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click-on Exit click-on Exit.. If you have not saved  saved  your spreadsheet, a reminder box will appear asking you to do so. so. 

Retrieving Spreadsheets

When you need to return to a spreadsheet, you first load Excel, Excel, as you did originally originally   (Page 1). When Excel is on the screen, click click-on File File in  in the menu bar then click click-on -on Open Open.. The following Open Open menu  menu screen will appear:

Click on Click  on the down arrow to arrow to the right of the Look in:  in:  box (Sim (Similar ilar to the arrow arrow in the Save in: box – see top arrow). arrow). Click-on the 3 ½ Floppy (A:), or the drive or

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folder you chose. chose. Files saved on a disk or in in a folder will appear in th the e box below. Click-on your Click-on  your file (MYBUDGET (MYBUDGET), ), and then click click-on -on Open Open.. Your file will open. You could also double-click quickly on the file to open it. it .

Also, if you have not done so already, move your cursor slowly over the "buttons" located below the menu bar. bar. You will notice a little box appears box appears that tells you what these buttons do. do. These little little boxes are are called Text Help  Help  boxes. Many of them will save save   you extra ―clicks ―clicks‖‖ by using them. Notice Notice,, that under File File   and Edit Edit   in the Menu bar, bar, there are a small folder (Open)  (Open)  and a diskette (Save).. Clicking-on them will take you directly (Save) directly to Open a and nd Save.  Save. 

Adding Numbers

Next method we wanthas to its learn learn how to add ad d numbers. There are several ways ways to do this. Each advantages and disadvantages.

To do this, begin by moving moving your  your cursor to cell C9, and clicking clicking-on -on cell C9.

Always move to the cell where you want the answer to be located.  located.  TYPE-IN METHOD

We want to add add the  the three numbers in cells C6, C7 and C8. C8. To use this method  method  type-in (using type-in  (using the keys on the keyboard) the following in cell C9 C9::

= C6 + C7 + C8

Your spreadsheet should look like the image to the right as you are typing in this equation. Note: you

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don’t have to use capital letters –  –  we only did this because they are easier to ―see‖ in the tutorial.

Now –  tap tap   the  the  Enter key. Then, click on click  on cell C9 C9   again again.. The total total   of these cells will now appear appear   in C9.. C9

When you have completed typing your equation, you will see this see  this formula formula in  in the area below the menu bar. bar.

Change  the number in cell C6 Change  C6   to 500 500   (and tap Enter). Enter). AUTOMATICALLY recalculates!!!

See how the total

THIS IS THE TRUE POWER OF THE SPEADSHEET !!! Whenever a number is entered in a cell the entire spreadsheet will automatically automaticall y recalculate. Something happened here. here. Notice how how you typed in an (equal sign) = before the cell location. location. If you had simply typed in C6 + C7 + C8, Excel would would have thought this entry was a  a  word (text)  (text)  and this entry would have shown as you typed it. Try this if you want. Any time you you ―create‖ an error in Excel, you you can simply rere type or edit the formula to correct the error. The Type in Method is Method is really easy if you have a few numbers and can see their cell locations on the screen. screen . If you have a lot of cells in the formula, which are on several screens, screens, this is not not such a great method. method. The next method method will work a lot better for numbers ―all over the place.‖  

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Subtraction, Multiplication, and Division You can put in  in  a (minus) - for subtraction, subtraction, (asterisk) * for multiplication, multiplication, and (slash)   / for division. (slash) division . As you become more capable we'll, build some nifty formulas – using these features. Point Method Move to cell C9 C9 again  again and click-on it. it. We'll now add the numbers numbers a second way. way. Tap the Tap  the Delete key on key on the keyboard keyboard to  to delete delete the  the current formula. formula. First, tap First, tap   the =  and then  then  POINT (move) the cursor cursor   over cell C6 C6   using the the   mouse,, tap mouse tap   the left mouse button on cell C6  C6  (you will see a marquee box go around the cell). Now tap tap   a +  and move move   cursor to C7 C7,, tap the the   left mouse button, and and   tap another +  and move   the cursor to C8 move to C8 and tap the the left  left mouse button (notice notice how  how as you " + and point " the " the addition formula is being built in cell C9), C9 ), now tap Enter. Enter. The same formula can be built built   using the arrow movement keys on the keyboard (except that you don’t have to click-on each cell as the cell is marked - as you move the arrows). Notice Notice,, as you are entering the cell addresses, addresses, that as you place another + in the formula formula,, that the cursor cursor   ―returns” notice,, as you point point to  to each cell cell that  that ―returns” to cell C9. C9 . Also notice it is highlighted highlighted   by a ―marquee ―marquee box.‖ box.‖ This ―tells tells‖‖ you what cell cell   you’ve pointed to to.. Pretty neat! This method is good when good when you need to move to numbers that are spread out all over the place. place. Some people people like it best and use it it all the time -- it's your choice. Function Method Move again Move  again to cell cell  C9 C9.. Delete Delete the  the formula formula by  by tapping tapping the  the Delete key again. key again.

Now type =SUM( SUM(  

in  in 

the

following:

[This tells Excel that Excel that we are going to sum sum some  some numbers numbers in  in a RANGE  RANGE which  which will follow the =SUM(.] There are two ways to ways to put in this range:

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Arrow Key and Anchor Method: Method: With the keyboard keyboard   arrow keys, move the cursor to cell C6. C6. As you move you will notice that the cell cell   where the cursor is located appears appears   after after the  the =SUM(. =SUM(.   When you get to C6 C6 tap  tap the  the  .  (Period) Key. This is called an ANCHOR and holds holds   one end  end  of the RANGE RANGE   in place. You will notice that a C6:C6 a C6:C6 appears in the formula the formula area under the button bar. bar. This is a one cell range. range. Now move, with the arrow keys, to cell C8. C8. See how cells C6, C7 and C8 are highlighted. highlighted . This indicates the Range is C6:C8. C6:C8. Excel assumes, logically, that these these are the numbers numbers you want to add. Now  Now  tap  tap  Enter Enter.. The numbers still add, but now the formula reads =SUM(C6:C8) = SUM(C6:C8) instead of =C6+C7+C8 like it did before. Mouse Method: Method: Move Move   again to cell cell   C9 C9.. Delete Delete   the formula formula   in cell C9  C9  by tapping the tapping  the Delete Delete  key. Type in =SUM( as you did before. Point Point to  to Cell C6 –  with your mouse cursor. cursor. Click and hold down the left mouse button  button  and and   move/drag   the cursor down to cell C8 move/drag C8.. (Cells C6, C7 and C8 should be highlighted.) Now tap tap  Enter Enter.. This =SUM Function is Function is a great way to way to add a lot of numbers, or a block/range of numbers. numbers. By simply anchoring, and using page downs, or using the mouse, mouse, you can highlight lots and lots of numbers to add quickly. However, since it only sums you can't do subtraction, etc. Point to cell C9 C9 again.  again. Tap Tap the  the Delete Delete key  key to remove the formula currently in cell C9. This is a really important DELETE, DELETE , since since what we’ll explain below won’t work correctly if you do not delete the formula in cell C9. Functions

There are a number of formulas formulas   built into Excel, Excel, like Sum Sum.. These formulas are called Functions Functions.. Below the Menu Bar  Bar  (see right right)) you will see a triangle to the right right    ―sigma‖ ∑ with a small down triangle of the sigma (see arrow arrow   on diagram diagram to  to the right right). ). Click on the down the down triangle. The drop down menu that you see see on the the right will appear. Move down to More Functions and click click-on -on More Functions. Functions. Two menu screens will screens will now appear appear   at the same time. time. An ―Office Assistant‖ Assistant‖ will appear (see image image   on left on left of  next   next page) page) and you can ask ask   it questions questions   (the little assistant may be a paper clip clip or just about about anything). anything). The Insert Function

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menu screen  screen  will also appear  appear  (see image image   on right right   of next page). page). menu screens work together to assist you when you are using functions.

The two

Let’s work with the Insert Function   menu screen. Function Click-on Click -on the small down arrow   to the right arrow right   of Or select a category:  category:  (see arrow at arrow  at left left). ).

In the drop down menu that appears you can see that there are all kinds of formulas (functions) that come with Excel spreadsheet (e.g. statistical, mathematical, financial, etc.). Instead of having to go to math,

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financial, or statistical tables in a book, you can enter data from your spreadsheet into the formulas and receive answers. This is a really great, timesaving feature. We’ll now show you how to use the Help features of Excel 2003 to work with and understand these functions.

Click-on Click -on All All in  in the drop down menu. menu.

The Select a function menu will menu will look like the image below. below.

Look at all the functions (formulas)! We’ll just go through how to use the addition formula (SUM) in this tutorial. If you need these formulas in in the future, you’ll know know they’re here.  here.  Use  the elevator bar  Use  bar  on the right right   side of the Select a function menu screen to move down the down the list until you see see  SUM SUM.. Click Click-on -on SUM SUM..

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Then click click-on -on OK OK..

Remember,, you clicked Remember clicked-on -on Cell C9 C9  – which was ―empty ―empty‖‖ because you deleted the formula in that cell.

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When you click click-on -on OK OK,, the Function Arguments  Arguments  menu screen (above (above)) will appear.. If you look appear look at  at the top of the screen  screen  in the SUM area, area, you’ll see see   that Excel 2003 has ―guessed ―guessed‖‖ that you desire to add add the  the numbers above cell C9  C9  –  where you clicked in in your spreadsheet. spreadsheet. Smart Excel! Excel! Notice Notice that  that it indicates that cells C6:C8  C6:C8  will be added (sum cells C6 through C8 –  the colon (:) means  ―through.‖ It also indicates the numbers in cells C6, C7 and C8 and give you the sum {300;50;150} = 500 (right arrow above). But it’s a little little unclear how Excel did this. The Help in in Excel Functions is excellent. click-on -on So, to see how this SUM equation works, we’ll go to Help. To do this, click Help on this function  function   in the lower left corner of the screen (see (see lower left arrow above). above).

On the right side of your screen you will see see   a Microsoft Office Excel Help window  appear (similar window  (similar   to the one above above)) that will show you how to use  use  this SUM function (or function (or any function).

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One of the really neat neat things  things about these Help windows is that there are examples examples   for each function. We moved down down the SUM help  help  screen screen using  using the elevator bar  bar  on the right right of  of the help screen. screen. The bottom bottom of  of the screen looks like the like the image image   at the top of the next page. page. Spend a few minutes looking at the SUM Help window and notice all of the features.

The bottom bottom   of the SUM help screen   looks screen like   the image like image   on the left.. left Notice   that it Notice gives you examples   from examples a small spreadsheet that has data in cells A1 through A6. It uses these numbers in the examples at the bottom of the help screen. When have reviewed all theMicrosoft help you care to Excel see, carefully click click-on the X  at the you upper right corner corner of  ofofthe Office Help  blue Help  bar-on bar to  to close close  the Microsoft Excel Help window. If you accidentally accidentally close close the spreadsheet, spreadsheet, simply reply yes to Save, and then re-open the spreadsheet as you did on pages 10 & 11.   11.

 

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The Function Arguments menu screen will still be on the screen. If the Office Assistant  Assistant  is still on the screen  screen  simply point to it and click click   the RIGHT   mouse button. A pop-up menu RIGHT menu will  will appear. Click Click-on -on Hide Hide.. This will put the Assistant away until we need it again

As you can see, in the area to the right of Number 1, 1, the ―Wizard‖ has “guessed” “guessed”   that you want to add the numbers in the range C6 to C8. C8. Now that you are becoming proficient with Excel, we’ll try something special. Carefully Carefully,, point point   to some “plain part,”  part,”  in the gray area above. Click  Click  and hold down  down  the left left   mouse button, and drag drag   the above SUM box  box  “away” “away”   so that you can see see   your numbers in numbers  in C column cells. cells. When you have done this, release the mouse button. Now click click--on the ―small box‖ on the right edge  edge  of the Number 1 area (see ―small box‖ arrow above). above). It has a little red arrow in arrow in it.

The below below  Function Arguments window Arguments window will appear appear..

 

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Highlight  cells C6 to C8  Highlight  C8  in the spreadsheet (click-on ( click-on C6, hold down the left mouse button, and drag until the three cells are highlighted). highlighted). A “marquee” “marquee”   will begin to flash flash   around the cells, indicating they are highlighted (left ( left arrow above). above ). The Function Arguments area will appear as above. above. Now click click-on -on the small button  button  on the right right   of the cell cell   (see right arrow above). above). The numbers will numbers  will show show in  in the area to the right right   of Number 1. 1. Now, click click-on -on OK at the bottom the  bottom of the Function Arguments menu screen. screen . You’ll see see that  that the SUM formula [=SUM(C6:C8)] [=SUM(C6:C8)] shows in the formula area at the top of the screen. screen. This is a really handy method to highlight a ―group‖ of numbers you want to add.  add.  AutoSum METHOD - ∑  Since we add numbers more than any other operation in spreadsheets, Excel spreadsheet has an additional feature - Auto Sum.. Move to cell C9 Sum cell C9 again and again and tap the delete delete key  key to erase erase your  your last formula. Now look look at  at the upper area of area of the screen screen,, just below the menu bar, for a ∑ (summation) symbol button button.. Point to it and click with the left mouse button. WOW !! Automatic addition!! Notice  Notice  that the cells,, you’d logically desire to add, have a marquee cells around them  them  and that the SUM SUM   function is displayed in cell C9 C9.. You’ll need to confirm confirm that  that this is the correct correct   formula. So, tap tap   the Enter key  key  and the SUM function will now be set in cell C9 C9.. Any time time you want to add using using this this method just click-on the cell where you desire the total to be and click-on the ∑.

Now move to cell C17 and add the total Expenses in cells C13 to C16 using each of the four methods.

While you are in in cell  cell C17 C17,, go ahead and place a line at the top of cell C17 using C17 using the format cells – border method method that  that you learned on Page 5.  5.  Subtraction

 

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In cell A19 type-in Net Income. Income. Next, adjust the width of column A (Page 6). Click-on cell C19. C19. In  In  cell cell C19  C19 we  we want to subtract subtract (  ( - )the amount in for Expenses Expenses in  in cell C17 C17 from  from the amount for Income Income in  in cell C9 C9.. This can be accomplished by using either the Type-In Method Type-In  Method or Point Method. Method. Go ahead and do this. Don’t forget to tap tap the  the Enter key Enter  key to confirm confirm your  your formula formula.. The formula should look like =C9-C17  =C9-C17  More Cell Formatting We want our numbers numbers   to look better. better. To do this we'll include dollar signs and and   decimal points in points in our numbers numbers.. This is done by using the mouse. Point to Point to cell C6,, hold down the left mouse button  C6 button  and drag drag   down slowly to highlight cells   C6 through C19. cells C19. Your screen screen   should look like  like  the one at the top of the next page. page.

Now point anywhere in anywhere in the highlighted highlighted   area   and click area click   the RIGHT mouse button.. A pop-up menu will appear. button Click-on Click -on Format Cells (like you have done before).

Click-on the Number Click-on Number ― Tab‖‖ at the top of the  ―Tab Format Cells menu screen. screen. Point to Currency and click click-on -on Currency.

 

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Notice several things.. things The right side  shows side the number of decimal places. The 2 is  is the default for cents. We'll use 2. 2. Notice above the above  the Decimal Places that Places that there is a sample sample of  of what our number will look like.. like At the lower right it  it  shows how negative numbers can appear, depending on your choice. choice. When a negative number number is calculated, it will appear with your choice. Now click click-on -on OK OK.. All the numbers now have $. If you have large numbers that are  are  "too wide"  wide"  for for   the current column column   width you will see  see  some ######## some  ######## in the in the cells cells where  where these numbers are located. If this occurs in your spreadsheet, go ahead and widen widen the  the columns as you did previously (Page (Page 6).

 

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Your spreadsheet numbers should now look like the one on the left.

Division and Percent Now move to cell A21 A21 and  and type in the word Percent. We're going to calculate a fun percentage to show you how division works and give you some more practice with numbers. Now move to cell C21. C21.   Using either the Type-In Method or Method or the Point Method,  Method,  divide ( / ( / )  ) the amount for Income Income in  in cell C9 cell C9 by  by the amount for Expenses Expenses in  in cell C17.. C17 [The formula should look like =C9/C17]  =C9/C17]  This will give you a horrid number so why not put a percent symbol  symbol  with it. Now we’ll repeat repeat what  what we did above to format our $$$$.  $$$$.   Point to cell C21 Point to C21 and  and click the RIGHT mouse button. Point Point to  to Format Cells, then click   the  click the  Number tab, then then   click-on Percentage. Select zero zero ( O ) Decimal Decimal Places.. Click OK. Places OK. Ta Da !!! a %.

Copying

We could repeat what we did to this point and fill in the Income and Expenses for each of the remaining columns. There is a simpler way  way  to do this. Assuming Assuming   our income and expense amounts amounts   are about the same, same, throughout  throughout the months, we want to copy the amounts amounts   in Column C to C to Columns Columns  D, E and F. F. This will require two “steps.‖ “steps.‖

 

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Move your cursor to cell  Move your cell  C6. C6. First, we'll highlight what we want to copy; copy ; next we'll tell the spreadsheet where we want to place what we've copied. copied . So, point to C6, hold down the left mouse button and drag down the column until cells C6 through C21 are C21 are high-lighted. Your highlighted area should area should look like the like  the one on the left left..

Now, point to Edit to Edit in  in the Menu bar. bar. Click the Click the left left button.  button. Point to Copy Copy   in the menu that appears. Click Click   the left left   button. The menu disappears.

You will notice notice that  that once again, when you highlight highlight   an area, a marquee  of running lights moves around marquee  around   the copy area. area. So, you’ll know you highlighted the correct area (image ( image on  on right right). ).

Now we'll tell the program where to copy  copy  the information. information. Point to cell D6, click and hold down the left mouse button and drag down and to the right to cell F21 (This F21  (This will highlight three columns -columns  -- OCT, OCT, NOV, DEC DEC -- to copy to.). to.). When you have finished your highlighting, your screen should look like  like  the one at the top of the next page. page.

 

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Now point to Edit in the Menu Bar again  again  and click click   the left button. Point to Paste.. Click left Paste left   button. Wow !' All those numbers and dollar signs and formulas - EVERYTHING EVERYTHING - was copied in a flash!! That sure saved us a lot of time.

 

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Note:

You can also utilize utilize the copy and paste buttons buttons in the button bar to do this if you desire.

Change  a few numbers  Change  numbers  in each each   of the months months   in both both   the income income   and expense   areas to see how the spreadsheet works. expense works . (This will make the graphs we’ll create more realistic when we create them later in the tutorial.)   This would be a great time to Save again. Now for something to do on your own.

Entering formulas in the Monthly Totals Column

Move to cell G6 G6 under  under the title Monthly Totals. Totals. Choose one of the formulas you learned earlier to add  add  each of the amounts  amounts   in Parents for Parents  for the four months. months. Use any of the four methods you desire. desire . Your spreadsheet spreadsheet   should look like the like the one to right right,,  just before you copy the formulas. formulas.

 

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After you have completed your formula copy copy it  it to cells G7 through G19. G19. You will see some "stuff some "stuff (zeroes)" in (zeroes)" in cells G10, 11, 12, and 18. 18. This is because there was "nothing "nothing there" there" to add add.. So, go in and clean-up clean-up these  these cells by deleting the zeros in these cells.

Next, go to  to cells G9 and and G17  G17 and  and underline underline like  like you did before (Page (Page 5). 5).

Copying Percentage Formula

Notice  that we didn‟t copy  Notice  percentage   formula copy  the percentage when we started this last copying effort. If we had copied a SUM formula, it would have added the four percentages. pe rcentages. We don’t want the sum of the percentages. We want want   a percentage percentage   of just the Monthly Totals. So, we need to copy this percentage separately. Now, copy copy   the percentag percentage e formula in cell F21 F21 to  to cell G21 G21.. Now put a $ in cells G6 through G19 if G19 if you need to, and a % in G21.. Your spreadsheet column G  G21 G  should look something like the image on the right right  

This would be a great time to Save again.  again.   Absoluting (and multiplication) multiplication) There are times, when we are working with a spreadsheet, that we do not want a want a cell to "roll" "roll"   to the next column  column  when we use use   the copy copy   feature of the spreadsheet –  like it did in our our last copying exercise. To stop stop   the cells cells   from  ―rolling  ―rolling‖‖ we utilize something called absoluting absoluting.. The foll following owing is is an illustration of absoluting. Go to cell A23 cell A23 and  and type-in Number Number..

Go to cell A25 A25 and  and type-in Result type-in Result..

Go to cell C23 C23 and  and type in a 2 – and and tap  tap the the Enter  Enter key. key.

 

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We'll now create a formula to formula to multiply our number times times Net  Net Income. Income. You may use either the Type-in Type-in or  or Point  Point   method. Go to cell C25, C25, and  and type-in a formula to multiply cell C23 times cell C19. C19 . The formula should look like:

=C23*C19   =C23*C19

The result in C25 C25 should  should be two times the net income in cell C19. C19 .

Now copy copy   the formula in cell C25 C25 to  to cells D25, E25, F25 and G25. G25 . Your row 25 should look similar to the one below.

Point  to each of the cells  Point  cells   D25, E25, F25 and G25. G25. Notice, as you click on each cell and look at the screen, how C23 (the cell with the 2) "rolled" and became D23, E23, F23 and G23 (which are blank blank - this caused the "0's" "0's"). ). A blank   times blank times   a number is a ―0.‖ We We want the 2 to be in each formula and not to "roll".  "roll".  To do this we utilize something called Absoluting Absoluting or  or Anchoring Anchoring.. Go back to cell C25 C25.. Now we'll enter the formula again, again, but a little differently   differently (to anchor the 2). 2). Type-in a =C23 Type-in a =C23 (or  (or you could type = and point to C23). NOW, tap the F4 key. key . Notice,, in the Edit bar  Notice bar  at the top of the screen, screen, that the =C23 changes to: $C$23.. $C$23 (This tells you that cell C23 C23   is absoluted absoluted   or anchored anchored.. The  The  "$'s"  "$'s"  indicate the indicate  the absoluting absoluting.) .) Now finish the formula by formula by typing in or pointing *C17 * C17   as before. Tap Enter Enter.. The formula should look like:

=$C$23*C19 $C$23*C19  

Now copy copy the  the formula formula in  in cell  cell  C25 to C25 to cells D25, E25, F25 and G25  G25  again. Your row 25 should look similar to the image below.

The numbers should now be correct be  correct.. Point to cells D25, E25, F25 and G25 (like G25 (like

you did before). You will notice the "$'s" have copied copied   the =$C$23 =$C$23   to each cell  

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(absoluting) and the Net Income Income figures have rolled rolled as they should. should. Absoluting is something you should know and understand. Pause and reflect --- Look at all you you have accomplished. accomplished. If you want go in in and change some more numbers or change the income and expense titles to something you feel is more fun or appropriate, please do so. This would be a great time to Save again.  again.  The next important lesson is to learn how to print. steps.

This done with a few easy

Printing   Printing First, move move to  to cell cell  A1 A1.. All of the Windows spreadsheets spreadsheets   try to figure out what you want to print. print . they're right right,, sometimes they're wrong wrong.. So........ The most important thing with printing is to tell the printer what to print. Unlike a word processor, you may need to need to highlight highlight   what you want to print. For the moment, we’ll assume that Excel 2003 will ―guess‖ correctly, and that and that you have not ―clicked‖ somewhere that will cause a problem. If you do have problem, which we’ll know in a second, we’ll show you how to take care of the problem a bit later.   It's usually a good idea to see see what  what our printout will look like –  before you print it. it. First, we’ll use a Print Preview  Preview  to ―see see‖‖ what spreadsheet like. To do this we’ll  to click-on click -onPrint the  Print  our Print Preview Buttonlooks Button    in the Button Bar Bar. . Point oint  the Print  Preview button and click and click on it.  it.   A picture, picture, of  of what our printout will look like, like, appears appears on  on the next page. page.

At the top top of  of the Print Preview screen you screen you will see see the  the button bar above. above. We’ll use a number of the buttons on this bar to assist us with our printing.

Sometimes

 

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Notice  that the Next Notice  Next   and Previous Previous   buttons at the left end of the bar  bar  are not highlighted with highlighted  with text –  they they are just just gray. This means means that  that the buttons are not indicates that  that we are OK OK with  with our spreadsheet – it is all on one “active.”   This indicates “active.” page.. If we saw that the Next button was active, this would page would mean that there are other pages to our spreadsheet. If you’ll you’ll look look   at the lower left corner of the  the  Print Preview screen  screen you’ll see: Preview: Page 1 of 1.  1.  This confirms confirms that  that our spreadsheet is on one page. page. If you do not see this “combination,” we‟ll show you how to take care of it later. If you do see this combination, combination , click-on the the Print  Print button. Click Click-on -on OK OK in  in the Print menu screen that screen that appears. Label this printout as: printout as: Default Spreadsheet Printout.. Printout

Next, notice that an image of your spreadsheet appears  Next, appears  below below   the button bar (above).  (above).   

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If you move your cursor over the spreadsheet, spreadsheet, you’ll notice notice   that the cursor changes from changes  from an arrow arrow to  to a tiny magnifying glass. glass. If you click click the  the left mouse button,, your magnifying glass will “zoombutton “zoom-in” on the exact spot where where the magnifying glass is located. located. If you click-again click-again,, it will zoom-out zoom-out.. Try this a couple of time. It is a really handy feature. feature. Now click click-on -on Setup Setup in  in the top button bar. bar.

The Page Setup menu screen at screen at the top of the next the next page will will appear  appear..

Notice that the Page Setup menu Setup menu screen indicates indicates that  that you are in Portrait Portrait view.  view. enhance   the spreadsheet to make it a bit more presentable. presentable. In the Now we’ll enhance Orientation   area click Orientation click-in -in the small circle  circle  in front of Landscape (see arrow above).. The spreadsheet above) spreadsheet will now now print on the the page as indicated. indicated. Next, in in the Scaling area, click click-in -in the box to the left of % normal size. size . Using either the

Scaling area, Scaling  area, click in the box to the left of % normal size. size . Using either the  

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 ―up/down”  ―up/down” arrows, arrows, or  or  by typing  typing  in the information, change the size to 125 125.. Then click-on OK OK.. Your spreadsheet will now be larger and fill the paper more appropriately. Click Click-on -on Print   and when this spreadsheet comes out of the printer label it: landscape –  Print enlarged to 125 %. %. Go ahead and adjust adjust   the ―size‖ of your spreadsheet so that it becomes too large  large  to fit on a single single page. page. Set the Scaling Scaling to  to 200 200 and  and click click-on -on OK OK.. When you return to the Preview screen, the Next Next   and Previous Previous   buttons at the top will now be active,, and you’ll see 1 of 3 or 4 pages in active pages  in the lower left corner of corner of the screen. Go ahead and click-on the the Next and Previous buttons to get a ―feel‖ of the ―size‖ of your spreadsheet. If you click-on click-on Print (please don’t do it), you’ll get these 3 or 4 pages. If you made a mistake mistake when you created the spreadsh spreadsheet, eet, you might might see that you have 58 pages in your spreadsheet! Now, click click-in -in the small circle to the the left  left of  Fit   Fit 1 page(s) wide by 1 tall in the Scaling area Scaling  area and make sure that 1 page  page  is set. Excel 2003 will now return return your  your spreadsheet to one one   page. Try other things here. Work with the Margins, Header/ Footer, and Sheet tabs at the top of the Page Setup menu screen. Any time you desire to print, go ahead and do so. This will give you a feel for how the spreadsheets will print. When you are are finished, simply click-on Close Close and  and you will return to your spreadsheet. spreadsheet. Many folks ask how to center a spreadsheet on the page. page . This feature is located in Margins Margins at  at the bottom of the Margins screen. Simply click-on Margins at the top of the Preview screen or on the Margins tab when you are in the Page Setup screen. Many folks also ask about how to place gridlines gridlines and  and show the row and column headings   (A, B, C and 1, 2, 3) in their spreadsheet printouts. headings located on the Sheet tab in the Setup screen menu.

This feature is

Cure for the problem – if you have too many spreadsheet pages. Simply click click-on -on cell A1  A1  and highlight highlight   your spreadsheet down through cell G25.. This time however, after you‟ve G25 highlighted A1 through G25, click-on click-on   File in File  in the Menu Bar and Bar and then click click-on -on Print.. In the lower left corner  Print corner  of the Print menu screen  screen  you will see see   an

area area that  that looks like the image onthe theleft of Selection. right. right . Click Click-in -in the small circle to Selection . This indicates to Excel  

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that you only want to print the area you’ve highlighted. Click OK. OK. Only the section that you’ve highlighted highlighted will print. You can still modify your spreadsheet if you desire. desire. Once you’ve clicked by Selection, you may click-on click -on the Preview button in the Print menu screen and you will see a preview of your highlighted area. Follow the instructions above to modify as you desire. Now we'll call it a day and close close Excel 2003 for for Windows. First, let's save let's save our  our work one more time. If you  you  forget, Excel will remind remind   you to do it. it. What a nice program!! Point to the Edit Edit   menu and click the left button. Point to Exit Exit.. button. That's it for for now. now.

Click   the left Click left  

When you return, we'll retrieve our work and do some really neat graphics. open your spreadsheet again, follow the instructions on Pages 10 and 11.

To

Graphics This will be a lot of fun fun.. We are now going to turn your spreadsheet numbers into graphics -- bar charts, charts, pie charts, charts, etc. This will greatly assist you when when you display and explain your work. Before we do this there are a couple of essential Before we essential   steps steps.. First we have to tell tell an  an Excel 2003 "Wizard" what we want to chart and chart  and then were were we  we want the chart to go. First: in cell B9 type-in Income  (to replace replace   the word Total Total). ). type-in   Income  Expenses in  in cell cell B17  B17 for  for the same reason.

Next, type-in type-in  

Something new.... Hold down the left mouse button and button and highlight cells B3 to F3.. Next HOLD DOWN the F3 DOWN the Ctrl Ctrl key  key at the bottom of the keyboard, keyboard, and while you are holding it down, highlight cells B9 through F9. F9 . You will now see two "ranges" highlighted. highlighted. Hold down the Ctrl again, and highlight cells B17 through F17. F17. These three ranges will make make up your chart. The x-axis x-axis will be made up of B4 - F4. And, the two sets of bars (series) will make-up Income and Expense. When you complete the above instructions, your screen should look like the one below.

 

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If your spreadsheet spreadsheet does not look exactly like the one above, above , please try again. again. This is a bit tricky and it often takes even experienced spreadsheet folks a couple of  ―tries‖ to get the highlighting highlighting just just right.

We’ll use the easiest method for method for our first chart (graph).

In the Menu Bar  Bar  click click-on -on to  to  Insert, Insert, then click click   on Chart. The Chart Wizard – Step 1 of 4 Chart Type  Type  menu screen will appear (like the one at the top of the next page). page).

 

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The Chart Wizard shows the various types of charts in Chart type: (on type: (on the left side of the menu screen).

Examples  Examples  of the selected chart type show on the right right under  under Chart sub-type.. sub-type We’ll stay with Column Column   and the chart selected for now.

Click  Next Click Next..

 

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The Wizard Wizard (on  (on the last page) page) shows you what you what your chart will look like. like. The selected originally  originally are shown shown in  in the Data range: area. range: area. If you did  ―ranges  ―ranges‖‖ you selected not highlight as indicated, your chart won‟t "look right." right." Your chart should look like the example above. above . If you click click-on -on the Series tab at tab at the top top   of the Wizard   screen, you’ll see Wizard see a new Wizard screen that shows you where the Income and Expenses series came from. Click Click-back -back on the Data range tab  tab  at the top. Now click click-in -in the little circle  circle  in front of Columns Columns.. The Wizard will indicate indicate that  that the chart has been ―rotated” ― rotated” 90 degrees and degrees and thus the axis has changed. This is   Click-back in the small circle in circle in front of Rows Rows.. Click Next Next   often called a ―pivot.‖  Click-back again.

The Chart Wizard Step 3 of 4 menu will appear: Titles (similar to the image above). Click Click-in -in the blank blank  area area under  under Chart  Chart Title. Title. A flas flashing hing cu cursor rsor will appe appear. ar. Type-in Typein your name with an apostrophe („) s and the word Budget (ex. Janie's Budget).  Budget).  Now, click click--in in   the area area   under Category under Category (X) axis: and axis: and type in Months.. Next, click Months click--in in the  the area area under  under Value (Y) axis: and axis: and type in Dollars Dollars.. You probably noticed that as you entered these titles, the chart in the area on the right of the Wizard changed to give you an ―instant‖ preview of your final chart. You will also notice that there are several tabs tabs at  at the top top of  of the Wizard. Click Click-on -on each each of  of the tabs tabs   and see see   what ―they do‖. Notice how some change axis and put in grid

lines. The legend legend is  is the small box on box on the right right,, which indicates indicates what  what the colors colors    

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of the ―bars ―bars‖‖ represent (Income and Expenses). Click Click   Next Next   one last time. The Step 4 page of page of the Wizard will now appear appear (image  (image at the top of the next the next page) page)

where you  you want to put put   This is the final Wizard page. You’ll notice that it asks you where your chart chart.. Since this is your first chart, it is best if you select As a new sheet:  sheet:  (see arrow above) above).  This will put your your chart chart on a new tab called tab called Chart 1. 1. Now click-on Finish Finish,, You’ll see that you chart has a tab of its own at the bottom of the screen, and ―fills‖ an entire screen. There's your chart. Again, notice notice that Exc Excel el created a new tab  tab  at the bottom of the spreadsheet that says Chart 1. 1. Any time the numbers change on Sheet 1, the bars in Chart 1 will reflect the change automatically!  automatically!  Click Click on  on the Sheet 1 and Chart 1 tabs to tabs to get the feel of going back and forth between the data and the chart. chart. After you you make your changes, changes, click click on  on the Chart 1  1  tab tab   and you’ll see how the chart has changed. In Excel Excel   2003 2003,, when you save your spreadsheet, you you   also save your graph. Your graph is saved wherever you are working in the graph. Changing (Renaming) Excel 2003 Tabs If you would like to have logical names for your Excel 2003 spreadsheet tabs –  rather than Sheet 1 and Chart 1, we’ll now show you how to do this.  this. 

At the bottom   bottom of your spreadsheet   you will see you spreadsheet tabs   (like the image tabs image   on the right). right ). To change the name of one

 

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of the tabs, place your cursor over a tab and tab  and click click the  the RIGHT RIGHT mouse  mouse button. We’ll change the name of Chart 1 first.  first. 

When you click the Right mouse button the drop down menu screen to the right will appear. Choose Rename. Rename. When you choose Rename, the Chart 1 tab  tab  will ―turn ―turn black‖‖ – like black image on  on the right right.. As soon as you see – like the image this, type in the name you want for your chart. chart . We typed in typed  in Budget Chart. Chart. As soon as we began typing, the tab name changed. When we finished, our chart tab looked like the one on the right.

Go ahead and name your Sheet 1 tab something more logical than Sheet 1. We named our Sheet 1 tab Budget Data.

Note: We are about to do some things which could mess-up Note: We mess-up   your graph. If you do get "messed-up"  "messed-up"  in the graph - don't save again. again. Simply Close Close   the worksheet and DON'T SAVE.  SAVE.  Open Open the  the worksheet again and you will be in a nice neat graph where you can experiment some more. Click on the Budget Chart (or whatever you named it) tab. Click-once on your title  title   at the top. A ―box box‖‖ with little squares  squares  on the corners will appear. These are ―sizing grabbers‖. When you move the cursor over them you will notice that the cursor changes to small, directional arrows. If you click, hold down the left mouse button, and drag when you see these arrows, you will notice that the Title Box gets larger or smaller as you

drag. Next, click click-on -on the name of your budget  budget   

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until you get a flashing cursor  cursor  somewhere in the title. With the arrow movement keys, keys, or mouse mouse,, move move to  to the end of the title, title, to the right of the "t" in Budget, and tap Enter tap Enter.. Type in Fall 2003. 2003. Now click click at  at the beginning of your name, hold down the left mouse button, and drag to highlight the first line of the budget title with your name in it. it . Keeping the cursor cursor on the dark dark area, click the click  the right mouse button. button. Click Click-on -on Format Chart Title. Title. Change  the Font Change  Font   to Times New Roman  Roman  (by moving up and down with the arrows) or any font that you li like. ke. As you change change things you you will see the results results in Preview on the lower right. Change the size to 20. 20. Change the color color if  if you want. Click  OK Click OK.. Click-on the upper right hand corner of your gray graph area. Click-on area . You will see  see  little squares now squares now appear at the the four corners and sides of the graph ar area. ea. Point to the upper right corner square and square and move the cursor until you see an arrow with two heads  heads  . Hold down the left mouse button and drag down and to the left  left  then let let go. Your graph graph will get smaller get smaller.. Now point point somewhere somewhere in an open gray area of area  of the graph (not on one of the bars) and click click again.  again. Hold down the left mouse button and button and drag the graph area so it looks more "appropriate". Click-on the Legend Click-on the Legend on the right right (box  (box with Income and Expenses). When you see right  in the the corner ―grabbers,‖ make the Legend box a bit larger. larger . Then click right  Legend area. area. Click Click   Format Legend. Legend. Click the the   Font tab. tab. Make the  the  font bold and size and  size 14. 14. Click Click  OK OK..

If you desire desire to  to change the colors of the Income and E2003ense bars  in the graph, simply move the mouse over one of the bars and click click the  the right right mouse  mouse button. Notice Notice all  all the bars bars with  with the same color now have a little square in the middle of each bar. bar. The right click ―marked marked‖‖ the bars. Series. Choose a color you like and Series. like and then click OK.  OK. 

Click Format Data

Now let's look look at your graph graph and then then print it. Go to File to File - Print Preview. Preview. If you like what you see go ahead and print print   the graph. If not, close Preview and make some more graph changes.

Whenever your graph graph   is visible visible,, you can point point   to any area  area  of the graph, and click the click  the right right  mouse button on button on the area, and edit edit that  that particular area. You can

also click click--right in the chart chart  itself. In the menu that appears, click click-on -on chart type  type  and then select a different type of chart. chart.  

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3.14 Database – Ms Access Using Access 2003 for Windows 2000/Me/2003 Starting Access 2003

Double click on the Access 2003 icon on the Windows Windows desktop  desktop (see right), right), or click click-on -on the Start Start   button in the lower left corner   of the screen, then click corner click-on -on Programs, and then click click-on -on Microsoft Access.. Access

The following Access 2003 Getting Started Task Pane  Pane  will appear appear   on the right side  side  of your Access 2003 screen. screen.

For Access 97 and and   2000 users, users, the Task Pane   is something new in Office XP/2002 Pane and 2003. 2003. It is used in all of the Office modules.. It replaces modules replaces many  many of the Microsoft Menu Screens, Wizards, and Catalogs that Catalogs that were a part of the Office 97 and 2000 screens. Once you get used to the Task Pane, and its flexibility, we think you’ll like it. There are a lot of Task Panes in PowerPoint 2003, FrontPage and Publisher 2003 – because they are so ―graphic‖ in nature. There are few Task Panes in Excel and Access 2003. In the Open area of the Access 2003 Getting Started Task Pane, Pane, click click   the left mouse button on button  on Create a new file. file .

 

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The New File menu screen at screen  at the on the right right will  will appear when you click the left mouse button on Create a new file.

Click– Click –on Blank database. database.

Saving your work  work  One of the unique unique   things about Access Access database  database is that it requires you to save save   your database database  as soon as you enter the program. program. You can save save your  your work on a floppy diskette in diskette in the A: Drive, or on your C: Hard Disk, or in some other drive, please save to these areas and substitute your Drive in the instructions. instructions. A File New Database  Database  menu screen, similar similar   to the one below, below,   will be on your screen. We’ll have to do several ―things‖ to set-up set-up this screen to save your

database.  

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In the upper left corner  corner  of the File New Database  Database  menu screen that appears, you will see see a  a Save in: in: area (see (see upper left arrow above). above). Click Click-on -on the small down arrow on arrow on the right right and  and it will show you the various disk drives available  available  on which you can save (see ( see right upper arrow above). above). Point to the drive on which you want to save your database, and database, and click-on it. it. If yo you u choose the 3½ Floppy ( Floppy  (A: A:), ), make sure you have a formatted disk in the A drive. drive. If you choose the C: drive, choose the folder in which you want to save by double clicking on the folder. Your selection selection should  should now appear appear in  in the Save in: in: area Next click-in click-in the  the area area to  to the right right of  of File Name:. Name:. Delete Delete any  any text text that  that is entered in the area and then type-in the word  word  PERSON as shown shown at  at the bottom of the above image (see lower left arrow). arrow). Now click-on click-on the Create button  button  or tap the Enter Enter   key as shown shown   on last page  page  (see lower right arrow on last page). page). The following person: Database menu screen should screen should now appear appear..

Creating a Table  Table  You will notice, notice,   in the person:Database menu screen, screen, in the left border:

Tables, Queries, Forms, Reports, Pages, Macros, and Modules. Modules . You will notice   at the top of the screen: Open, Design and notice and   New. New. You may create  

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multiple Tables (Databases), as well as multiple other items associated with the items in the the left border. As you create them, they will be shown in the "white" "white" area. In other words, the PERSON database can be made-up of, or contain, many other databases (tables), reports, queries, etc. For now, now, we'll do a basic database (table) creation. creation. Later, you can try Tab Table le Wizards when you have the "feel" for creating a table. To begin begin   designing designing   the database database,, please click-on the Design (see   “button”   at the top of the person: Database menu screen (see “button” arrow on last page).  page). 

You should now see a Table1: Table design Table design screen similar similar to  to the one below below.. If the Table: Table1 image Table1 image does not “fill” the screen, screen, click click-on -on the small square  square  between the ―minus ―minus and the X‖ X‖ in the upper right hand corner  corner  of the screen (see arrow and arrow and image image on  on right right). ).

Notice, under Notice, under   the Blue Bar at Bar at the top top of  of the design screen that screen that there are (3 ( 3) things: Field name, Data Type, and Description, Description , and, in the lower half of the window; Field Properties (see arrows in image below).

 

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Next you will be creating creating the  the fields fields that  that make up a database database.. This is similar to creating a blank personnel form (on paper) that will be "filled-in" for each employee (Name, Address, Phone Number, etc –  are called fields fields   in a database). These "forms forms"" are called records records in  in a database. There will be a record, record, or form, for each employee. All the forms, together, make up a Table (database). So let’s create a personnel database.

 

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Significant Note: Note: When creating creating a  a database database   it is always best to ―break ―break down‖ down‖ a field field  into its ―smallest parts.‖ For example – Name would break down into First ―smallest parts.‖ Name, and Last Name Name (you could also also have Middle Initial, Title, etc.) Address would break down into Street Address, City, State, and Zip (you could also have Apartment Number, Number, etc). Because we we are working working in Access Access 2003 it will be very simple to ―put the fields back together‖ with a few mouse clicks when we need to do this. this. Trust us. us. This will save save you a lot of time later on. on.

Look at the at the image image on  on the right right.. Click-in Click-in   the area area or  or space space   under under   Field Name and Name and type-in   Last Name.  type-in Name.  Tap Tap   Enter or clickin in the  the area area to  to the right right under  under Data  Data Type. Type. The cursor cursor   now moves moves   to the right under Data Type. Type. Notice Notice,, that Text appears as appears as the default default   (and a box box   with a downarrow   appears arrow appears   in the right side  side  of the box). box ). Click Click-on -on the down arrow. arrow. Your design screen should look like the like the one on the right right.. Now we’ll talk about Data Type.  

Data Type Text

You may type in any alphabetical/numerical data that you desire - up to a maximum maximum of 255 characters. characters. As indicated, this this is a text field, so so you can't do mathematical mathematical calculations. Examples of Text data data are: names, addresses, stock numbers, room numbers, zip codes, etc.

Memo  Memo  characters. Number   Number

This field is for lots of text.

You can have up to 32,000

This field is for numbers where you want to add, subtract, multiply, divide, average, average, and do numerical numerical calculations. calculations. This field can be a very large size, so when we get to Field Properties, we'll talk about "sizing" this field so it doesn't take up to much "space" in storage.

Date/Time   Dates and Times. Date/Time Times. You may format format these later, as you may desire.

 

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Currency   Currency

Dollars ($). You may format these later, as you may desire.

AutoNumber   AutoNumber

This field is an "automatic" "automatic " counter that assigns a number each time you put data into a new field.

Yes/No  Yes/No  This is a "True/False" or "Yes/No" type of field. OLE Object  Object  This means "Object Link Embedding" which indicates you can insert a graphic, picture, picture, sound, sound, etc. Pretty neat to put a photograph photograph in a personnel record or a picture of an inventory item in the stock record (advanced stuff). We'll leave Last Name as Name as a Text Text   Data Type. To the right under Description Description you  you may make any remarks you feel are appropriate to someone who may want to know how/why you designed the field as you did. Now notice notice   in the lower lower part  part of the screen, under Field Properties, that Properties, that a box appeared   when you selected appeared selected   the Text Data Type. Type. This box is "tailored "tailored"" to  to  the Text Data Type Text Data Type that you selected selected above. Your Field Properties should look like the one below when below when you finish finish doing  doing the steps steps indicated  indicated below below..

Field Properties Field Size Size   Is currently set  set  to 50 50   characters. characters. So, click-

That's pretty pretty large for a name.

in in this  this area area and  and change change the  the number to 25 (you can make this larger  

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or smaller later if you have to). Format   Format

Now click click-in -in the Format Area. Area. activate Help Help..

Next tap tap   the F1 function key  key  to

Since you are in the Format Format   area, Help Help   will be "tailored "tailored to" to" this area. When the Help Window appears, appears, click click-on -on Text and Memo Data Types (Notice Types (Notice that you click-on different Data Types, depending on the Data Type you select). select). This gives you an idea of some formats. formats. We'll use one later. Now click click--on the ―X corner  ―X‖ in the upper right corner  of the Microsoft Access Help – Format Property Window to close close   it. Input Mask

We'll come back to this feature later.

Caption   Caption

Look at the Gray Help area to the right. Caption.

Default Value  Value 

We'll come back to this feature later.

It explains about

Validation Rule  Rule  We'll come back to this feature later. Validation Text  Text  We'll come back to this feature later. Required

Look at the Gray Help area to the right.

Allow Zero Length  Length 

Look at the Gray Help area to the right.

Indexed   Indexed

Look at the Gray Help area to the right and tap F1 (Help)

Unicode Compression Compression

Look at the Gray Help area to the right.

IME Mode

Look at the Gray Help area to the right and tap F1 (Help)

IME Sentence Mode Smart Tags

Look at the Gray Help area to the right and tap F1 (Help)

Look at the Gray Help area to the right and tap F1 (Help)

repeat   this process process   and create different Field Names and Data Now we’ll repeat Types   (as necessary). Type-in Types Type-in   the Field Names  Names  as indicated below below   and set them to them  to the Data Types and Types and Sizes indicated. indicated. Field Name Last name  name 

Data Type  Type  Text

Size   Size 25

(Already Completed)

First name

Text

20

 

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Social Security #

Text

15

We'll use an Input Mask for our our Social  Social Security Number. Number. Click Click--in  in  the Input Mask area in the Field the Field Properties area at the bottom the bottom of the screen the screen (see left arrow below). below).

Notice  there are three "dots" (...)  Notice  (...)  in a box on the right right.. Click Click-on -on the three   dots (see right arrow above). three above). An Input Mask Wizard will appear: appear: "Must Save Table First. First. Save Now?". Now? ".

Click-on Click -on Yes Yes..

A Save As  As  Window will now appear. We'll save our Table Table as Personnel Personnel,, so type-in type-in   Personnel in the area under Table Name:, Name:, and click click-on -on OK.. OK

Next, a Microsoft Access menu box will box will appear appear indicating  indicating There is  is No Primary

 

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Key  defined Key defined.. Click  NO Click  NO.. (Keying, or indexing, is somewhat advanced. description by searching in Help for Keying.)

You can get a good

The Input Mask Wizard  Wizard  will show show   you some Sample Masks  Masks  (you may scroll up/down to view them). We'll use use Social Security Number, Number, so click-on so click-on it. it. Your screen should screen  should look like the like the one below below..

Now Next at Next  at the bottom bottom of  of the Input Mask Wizard screen. screen.

click-on click -on

You will now see see a  a default number of number of 000-00-0000 000-00-0000 using  using dashes (-) between the numbers. numbers. You can use anything anything you want. want.

 

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We'll leave it as is, so click click-on -on Next> again (at the bottom of the Input Mask Wizard screen). On this Input Mask Wizard screen you’ll see two choices. choices. Click Click--in in   the little circle to the left circle to left of  of With symbols in the mask, like this:. this :. Sometimes, when we use Access data as a part part of mail merges or in labels, if we don’t save the dashes, they won’t appear in our document. So, it always a good idea to save dashes.

Click-on Next> Click-on  Next> again. again. Now click click-on -on Finish  Finish.. You will see see   some ―special ―special‖‖ numbers written written in  in the Input Mask area  area  for Social Security #. #. When you you begin to enter data in this field, you’ll see how this works. Your Field Properties area should look like the one below.

Now continue entering the following information in the Field Name and Data Type areas as we did above.

Street address

Text

25

City

Text

20

State

Text

2

 

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Here we'll use a Format  Format.. First make the Field Size Size 2  2 then  then click-in the area to the right of Format. Format.

A down pointing  pointing  arrow arrow,, like like the  the one above above   (see arrow) arrow), will appear on the right right side  side of the Format area. area. If you click click-on -on the arrow, the area will appear blank (that's because we haven't entered a Format). Tap the F1 key in the row of   Function Keys at the  the  top of the  the  keyboard. A Help menu screen ― screen tailored‖‖ to Format Format will  will appear appear )like  )like the one below) below)..  ―tailored

 

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Since we are working with  with  a Text Data Type, Type, click click-on -on Text and Memo Data Types (see Types  (see arrow above). above).   Notice that a >  will change any alphabetic character you Notice that character you type into all upper case letters. letters. Now point point   and click click   the ―X ―X‖ in the upper right hand corner of the Format Help Screen (notice that the Help Window closes "automatically").

Now type type   a  > in the Format Format   area. Your Field Properties area Properties area should look like  like  the one below below..

Continue entering the following information in the Field Name and Data Type areas as we did above. Zip

Text

5

Gender

Text

1

Insert a >  in the Format Format   area to make all gender  gender  entries become  become  capitals (like capitals  (like you just did for State State). ).

Favorite Number  Number 

Number   Number

(Note: this is the first Number field)

 

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Here we'll learn about Numbers, Numbers, the  the Validation Rule and Rule and Validation  Validation Text. Text. We'll limit the person's favorite number to a number between 1 and 999. 999. Leave the Field Size set Size set to Long Long   Integer Integer (Tap  (Tap the F1 F1   Function Key [Help] to view the different Number Field Size descriptions). descriptions ). After After   you have viewed   the Number Help screens, click viewed click   the small ―X ―X‖ in the upper right hand corner of corner of the Help screen to close close the  the Help screen. Now click click-in -in the area area   to the right right   of Decimal Places. Places. It currently indicates Auto.. When you click there Auto there you will see a little down arrow on arrow on the right right side  side of the area. Click Click-on -on the little arrow arrow.. Select ―0.‖ This indicates that decimal places are not allowed in the Favorite Number.

Next, click click-in -in the  the  Validation Rule  Rule  area. We'll "build "build"" a mathematical expression that expression  that will only allow numbers from from 1 to 999. Type in Type in the following expression (in expression  (in the area to the right of Validation Rule): > 0 and < 1000

This tells Access that the number entered must be between 1 and 999. You’ll notice notice that  that when you click click-in -in the Validati Validation on Rule area that area that three periods appear   just like they did in Input Mask. If you want to click-on the three (…)   appear (…) periods they will bring up an Expression Builder which you can use to create the mathematical formula above. Please note  note  that frequently, if you are really not

great at math, the Expression Builder can cause problems. problems . Sometimes, the Expression Builder will ―insert‖ an  in  in the formula. formula. If it does this, delete  

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the .. This will confuse Access, and will frequently cause the program to  ―stop‖ until you remove remove . So, if you want to look at Expression Builder, please do so. But – be careful. If someone does not  not  enter a number correctly, correctly, an error message will appear. Now we'll create an appropriate error message. message. area and type-in type-in::

Click-in Click -in the Validation Text  Text 

Favorite Number must be between 1 and 999.

When you finish all of the above, your Field Properties should look like the one below. below.

Continue entering the following information in the Field Name and Data Type areas as we did above. Date hired Date/Time In Format Format   click click-on -on the small down arrow  arrow  on the right side  side  of the Format area and choose Short Date. Date. In the Input Mask area Mask area click-on click -on the three dots (...), (...),  save the table, table, and again choose  choose  Short Date,, click Date click  Next> Next>,, click Next> again, again, then click click   Finish Finish.. (This will insert a / between the day, month, year).

 

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Your Field Properties should look like the image below. below.

Salary

Currency

In the Decimal Places  Places  Field arrow   on the right side  arrow side  and Notice the Default Value of   0 entered. We'll leave leave it at zero. zero. the one below.

Application Received

Properties area click click-on -on the small down select  0 (zero) –  this indicates ―no cents.‖ select  income will be inserted if no Salary figure is Your Field Field Properties Properties screen screen should should look like

Yes/No

We‟ll make this a “Yes/No “Yes/No” ” or “check box” field. When we begin entering entering data in the database, you‟ll see how this “box” works.  works.  

Point to and click click   on File in the  the  Menu Bar then then click  click on Save As.  As.  The Save As Window will appear and Personnel should appear under Table Name: Click Click-on -on OK OK.. You could also click-on click-on the small diskette Save Button if Button if you desire. Entering data in the database  database  At this point you will still be in the design window.. You have two choices. If you look at the window Button Bar just below the Menu Bar Area  Area   (File, Edit, View, etc.) you will see that the  the   first button on the left that has a small sheet of paper with some data on it (see

arrow on the right arrow on right). ). Point Point to  to this button button with  with the mouse and pause pause,, you will see a "Tool Tip" Tip" that indicates indicates that  that this button is the is the View Button. Button. This is logical  

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because you have been designing your table and now want to view the data that you have placed in the database (table). If you are familiar with spreadsheets it looks like a tiny version spreadsheet. spreadsheet. You can click click-on -on the View Button  Button  and go right into entering data in your table. However, it might be good to see how to enter data when we first open Access. Access. So, point and click click-on -on File  File in  in the Menu Bar, Bar, then click click-on -on Close Close.. You will return to the main database window where we started (PERSON: ( PERSON: Database). Database).

You should see the  the  Tables choice highlighted  and highlighted  Personnel Table highlighted. Notice that there are three Buttons at Buttons  at the top top portion  portion of the window which indicate: Open, Design, New. New. If you click-on New you can add another table table to the Person database. database. If you click click-on -on the Personnel Table (make (make sure that it is ―blue ―blue‖) ‖) and then click click-on -on Open Open you  you will open the table you created. You can now enter data. data. If you click-on Design, Design, you will be back back in the the design window and can alter your design. Note: if you find, as you’re entering data, that if you made a field too small, you can go to Design View and make the field a larger width at any time you desire. let's click click-on -on Open Open.. The Personnel Table  Table  will appear   on the screen. appear screen. If the window does does not fill the screen, point to the Expansion “square” in the upper-right corner directly to the right of Personnel: Table in Table in the blue blue bar. This will expand your your Table to fill the the desktop.

Move the cursor arrow over the buttons below menu bar . As you do, notice notice   that the "Tool "Tool Tips" Tips" will tell tell you  you what each button does. does.  

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Notice, below below the  the Button Bar, that Bar, that the fields fields   you created in created in your Personnel Table are displayed displayed   in what is called Datasheet View (see above). above). Notice Notice   the small ―button File  in the menu ―button‖‖ under File  bar.. It shows bar shows a  a small blue triangle, pencil, and a ruler (like like the  the one on the right right). ). This is a ―toggle ―toggle‖‖ which will take you back to Design View - if - if you need to make design changes  changes   while you are in Datasheet Datasheet view. If you go go back to Design View, you can then ―toggle‖ back to Datasheet view when you have made your corrections. Under Last Name  Name  you will see see   a flashing cursor; cursor; this means that you are ready to begin entering data. data. You may type the data and data and tap   Enter, tap Enter,   or click with the mouse in each field. field . If you make a mistake you may retype retype   the data. If you see a mistake later you can come back at any time and correct it.Under each field, type field, type the following in the area below the Field Name:: Name Field Name

To be typed

1.

Last Name

Butler   Butler

2.

First Name

Greg

3.

Social Security #

4.

Street address

100 Main Street  Street 

5.

City

Lynchburg   Lynchburg

6.

State

va   va

7.

Zip

24501   24501

8.

Gender

m or f  (your  (your choice)

9.

Favorite Number

123-45-6789   123-45-6789

2003   2003

10. Date Hired

7/01/1993

11. Salary

40000

As you are entering this data you will wil l notice notice several  several things. Social Security Number and and Date  Date Hired  Hired –  work.. work State and State  and Gender Gender  – 

see‖‖ your Input Mask You’ll ――see

you typed in small letters – notice notice how  how the Format Format (  ( > )

forced the forced  the letter(s) letter(s) to  to be capitals capitals.. Favorite Number  Number –  since the Favorite Number  Number  is ―too big‖ big‖ you will will   see your error message  message  appear. Click Click-on -on OK OK   in the message  

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Salary -  - 

screen and then create create a  a Favorite number that will work. work. notice how your Currency Currency   formatting created a $, commas commas   and periods.. periods

When   you have completed typing the When typing the information, tap Enter Enter   so the cursor will move down to the next next record. You are now ready to insert insert your second entry. entry. Note: When you tapped Enter, Access automatically saved  Note: saved  your first record. This can be confirmed by the display of the hourglass. hourglass. Also note: note: As you began began typing your your first record a small pencil appeared appeared in the left margin. margin. This indicates that you are "writing "writing to" this record record (editing). Below the pencil an *  (asterisk) also also appeared. This indicates that your next next record will go below the first. There are (2 (2) methods methods for  for entering entering  data into the database: database: 1. The method method you just just used is called Datasheet called Datasheet View method. View method. or 2. You can use the Form View method (we’ll create a Form in a bit later in the tutorial) tutorial). Exiting and Saving  Saving  Note: Anytime you want want to take a break  break  and exit exit   Access Access,, simply point point   to File in File  in the Menu Bar, and Bar, and click click-on -on Exit Exit.. If it asks Do you want to save?, save?, click click-on Yes Yes.. If it gives you a save file screen, screen, give it a name of your choice and click click   on OK OK.. You should should then then exit to the Windows Screen with no problems. problems. Since you have already named everything for this exercise, you should not have to name any files as you exit. Opening Access Database If you decide to Exit Access 2003, and then return to continue the tutorial, refer to the instructions at the beginning of this tutorial (Page 1).

A neat thing  thing  about Access 2003 is the Task Pane on the right side of the screen. screen . We used the Task Pane at the beginning of the tutorial

(Page 1) 1) to create a new database. Once you have created a database, you will see see   your database   in the Open database Open   portion of the Task Pane  

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(see arrow arrow and image to the right). tutorial Person, and it will open.

You can can simply simply click click-on -on the file file,, in this

Or, you can open the database the way you open many files. When Access 2003 opens, click-on click -on File in the Menu Bar, Bar, and click-on click-on Open. When the Open menu screen appears,, click appears click-on -on the small down arrow to the right of the Look in area   and choose area choose   the drive drive   on which you saved your database  database  (A: 3 ½ Floppy or your C: Hard Disk Drive). Then click click-on -on the name name   of your database  database  (e.g. person.mdb person.mdb)) and then click click  Open (at the bottom of the menu screen). Now follow follow the  the instructions instructions at  at the bottom of  Page   Page 14 to 14 to open your personnel table and table  and to continue entering data. data. Form View and Datasheet View  View   In the Button the Button Bar (just below the Menu Bar, to  to  the the right  right of Help, Help, is a button with a lightening bolt and a small form. form . This is the  the  New Object: AutoForm Button.. Point to it - make Button - make sure you have the correct button - then click-on it (see image below). A New Data Entry Form will automatically automatically be  be created created and  and appear.. appear

 

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The Personnel Personnel   Form Form   should look   something like the one on look the left left..

Since you are in the Personnel Personnel   Table,, Table the form will  ―  ―automatically automatically‖ ‖ bePersonnel created,  just like the Datasheet.. You will now see a Datasheet data entry form  form  window. If the form does not fill the screen, click-on the expansion square (see arrow above)  above)  to increase the size.  size.   Notice Notice   your first record appears. appears.

You may enter data  data  in Form View   the View same   as same in Datasheet View. View. To save save   this form form   click click-on -on File File   in the Menu Bar, Bar, then on Save As. As. The Save As screen will appear with Personnel Personnel   already in the image to the left left). ). Click Click-on -on OK OK.. Save Form „Form1 To: area (see image to

 

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The data entry form form is  is now saved as Personnel Personnel,, just like the Table. Notice, at at the bottom of bottom  of the Form screen, screen, that there is a status area (see below) that below) that tells you what record you are on. You can use the arrows to ―move‖ from one record to another, or select select a new record in which to enter data. data. Click-on each of the arrows to see how they work. Some will take you forward forward are back to the next or previous record, and some will take you to the beginning or end of your records. The arrow with an asterisk will asterisk will take you to a new blank record. record. Enter a few records to see how the Form View works.

When you first “open”  Database, you may “open”  your Person Database, choose  your favorite screen choose favorite screen to enter data: The data Form Form or  or Datasheet.. Click Datasheet Click-on -on either the Tables selection or Forms selection on the left left   of the window. Then, click click-on -on Personnel,   and then click Personnel, click   Open Open   to begin entering data in your choice. You can switch back and forth from forth  from the Datasheet entry to entry to the Form entry by entry by clicking clicking   on Window Window in  in the Menu Bar. Bar.

At the lower left corner  corner  of the menu  menu  screen screen,, you will see see   some text that indicates that you are either using Form or Datasheet View to enter your data.. data

This text indicates that you are currently in Form View (or (or   Datasheet View)  View)  using using the Personnel database. You can  

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“shift” back and forth between Datasheet View and form View by View by using the View button in button in the upper left corner of corner of the Access screen. The View View   button button   on the right right   indicates indicates   what ―view ―view‖‖ you are using: Design View, Form View, or  or  Datasheet View. View. You can move back-and-forth between views by views by clicking clicking-on -on the down triangle to triangle to the right of the button (see ( see arrow and image to the right) right ) and then choosing either Form Form   or Datasheet Datasheet to  to enter your data. Note:: When you are finished entering data and preparing to exit Microsoft Access, Note or Close the form, if you did not save before exiting, the program will ask if you want to Sav Save e the Form the Form.. This is up to you. you. You may may save save it with your choice of names and it will then show-up as a form when the Person Database Main Window appe appears. ars. Or, you can indicate indicate No, and re-create the form again with the Wizard. Important To record enough information so that you can see what a database does enter 24 or more records now. now . You may use either Form View  View  or Datasheet View.. View

 

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Querying the Database  Database  This is what a database is designed for: for: finding specific information  information  about some of the data data in  in the table table(s) (s) very quickly. quickly. A query is a search for general or specific or  specific data in a field or fields or fields in  in your database (e.g. the first and last names and birth dates of all employees, just the Jones’s, the people from CA, salaries > $10,000, etc.). In order to do this, this, we need to click on the fields we want to query.. So, let’s start by finding just Last Names in our table query table.. If you are not in  in  the  the  Database: PERSON  PERSON  screen screen   which shows shows   the Tables, Queries, etc., etc., go there by clicking clicking-on -on Window Window   in the Menu Bar  Bar  and then on PERSON: Database.  Database.  Also, if you have the Personnel Datasheet or Personnel or Personnel Form open (to open (to add data), close them before you you begin begin your queries. The Access Access   program sometimes becomes logically confused confused when  when you try to do queries when it ―thinks‖ you also want to add data. You may see ―error‖ messages if you leave the Form or Datasheet open.

Notice, at the left Notice, left   of the Person: Database   screen there is a selection Database selection   that indicates  indicates  Queries. Queries. Click-on it. it. Since we have not done a query before, double-click quickly on Create query in Design view or click click-on -on Create a query in Design view and then click click-on -on the Design button. button.

Two  new windows will now appear: Query 1: Select Query  Two  Query  and Show Table. Table. You will first first have  have to select the table(s) you desire to query. query. The Show Table screen   should look like  screen like  the one below below..

 

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Make sure the blue highlights are highlights are on Show Table and Table and Personnel Personnel.. Click Click-on -on Add  Add (we'll talk about Wizards later). Then click click-on -on Close. Close.   The Show The  Show Table window will disappear, and the Query 1: Select Query window, Query window, behind the Show Table window, will appear appear by  by itself.

Click-on Click -on the expansion square in square in the upper right corner  corner  to enlarge enlarge  the Query 1: Select Query window. Query  window. Your screen should now look similar to the one below.

These areas are magnified below

Notice, in the upper half of the window,  window,  a small box  box  on the left indicates: Personnel.. At the Personnel the top is an an asterisk (* ) and ) and below below,, in an elevator elevator box,  box, are the fields from the Personnel  Personnel  Table Table   (you can move up-and-down the list as you desire). What we need to do next is place the Fields we want to query in query  in the lower the lower area  area  of the screen. Notice Notice   the lower area  area  on the left border.. The first row indicates Field:, followed by  border by  Table, Sort:, Show:, Criteria:, and and or:  or:..

In the lower half of the screen click click--in in the  the first cell to the right of Field:. Field:. We'll start with a query on  

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Last Name, State, Favorite Number  Number  and Salary Salary.. Now click click-on -on the down arrow and then click click-on -on   Last Name. Name. Notice Notice   how Last Name now appears appears   to the right right   of Field Field:: and a (check check)) is seen seen   in the Show Show:: cell (The means   that you will see means see   Last Names Names   in your query.). Notice Notice   also that, to the right of right  of Table Table:, :, that Personnel Personnel (the  (the Table from which we queried) is showing.

Your query screen  screen  one on the right. right.

should now look like  like  the

Now move to Now move  to the next Field cell on the right and, right  and, using the down arrow  arrow click click-on State State.. In the next two fields to the right, right , insert Favorite Number  Number  and and   Salary.. Your Query1: Select Salary Select Query screen screen should should look like this: this:

Now, look look   in the  the  Button Bar at the top of the screen. screen. In the middle of middle  of the bar you will see see an  an exclamation mark ( mark ( ! ) like the one on the right right.. If you move the cursor over it, the help help text box will indicate "Run "Run." ." Click-on the  the  ( ! ). This click executes your query. query.

 

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Your query screen should look similar to the one on the left.  left. 

Notice, Notice, the screen  screen  ONLY   shows the four ONLY fields that fields  that you queried. You can add add or  or remove remove  fields, fields, as  as you desire. To do this we need to return to return  to the Design View  View where we created this query. To return return   to Design View  View  click click-on -on the small small   button button   in the upper left corner of corner  of the screen screen that  that has the blue triangle, pencil, and ruler  ruler  (like the one one   on the right right). ). Then, simply click click-in -in the Field area  area  and select a new field  field  and it will replace replace   the old one. Or, click-on the field you want to remove   and tap remove tap the  the Delete key. key. Sometimes Sometimes you m may ay have a lot of fields fields and it will be too large for a single sheet of paper.

 

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To see see how  how your query query   would look, if look, if you print print it,  it, click click   on the  the  button  button  that has a piece of paper and magnifying glass (Print Preview - like  like   the one one   to the left).. While you’re in the Print Preview you’ ll left) ll see a little magnifying glass glass that you can move over yo your ur query. If you click the left mouse button once the magnifying glass will ―zoom‖ in and enlarge the view. If you click the left mouse mouse button again it will zoom out. To return   to your query, click-on return click-on   the  the  Close button just above the print preview piece of paper.  paper.   This will take you back to the Normal Normal View of your query.

Sorting the Database

If you are not in the Query Design Screen, Screen, you’ll need to be in that view. So, go go   to the Design Screen.. Notice Screen Notice   that the third row,  row,  in the  the  lower half   of the screen, indicates  indicates  Sort: (like the image image   at the right right). ). Click Click-in -in the Sort:: area under Last Name. Sort Name. A down arrow box arrow box appears appears;; click-on the down arrow.. Let's sort the Last Names  arrow Names  in Ascending Ascending   order. Click Click-on -on Ascending Ascending.. Notice that Ascending Ascending now  now appears in the Sort: area. Click-on the  the  ( !  ) to see the new query. query. Notice that the names names you entered are are alphabetized. alphabetized. Click-on the Design View button (triangle-ruler-pencil). (triangle-ruler-pencil) . Now change change the  the Ascending Ascending   under Last Name to (not sorted). sorted). On your own, try sorting some of the other fields. When you you are finished remember to set to set the fields to (not sorted) unless sorted) unless you do want to sort on those fields.

You may also sort  sort  various fields fields   in your database whenever you are in the Datasheet View, View, whether you are viewing the entire Table Table,, or a Query Query from  from the Table. Notice that the Field Names  Names  are shown at the top of each column in gray cells. cells.

 

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If you click-on one  one  of the gray area field names  names  (like State State), ), the entire column  (Field) turns ―black column  ―black‖‖ (like the image above). above). have ―marked ―marked‖‖ the entire column (Field).

This indicates that you

In the button bar  bar  that appears, appears,   when you are editing the Datasheet View, View, you will see two buttons with “down” arrows (like the image image on  on the right right). ). When you move move   the cursor over these two buttons a buttons a text help box help box will indicate indicate:: Sort Ascending  Ascending  or Sort Descending. Descending. If you click-on one  one  of the buttons, the Field Field   which you selected selected   (highlighted) will be sorted sorted   in the order selected. selected. Give this a try and see how it works. So, there are several ―ways‖ you can sort your Tables and Queries.  Queries.   Specific Queries So far we have listed everything everything   under each Field Name  Name  that we selected. However, many times you will probably want to find something  something  specific specific in  in your Table (database - e.g. people from a certain state or city, people whose favorite number is 7 or salaries between $ 20,000 and $ 50,000 ). This is fairly common sense, but it can get tricky tricky..

To get an idea of various criteria, criteria, you

might want to use, click on Help Help   in the menu bar. Then, click click-on -on Microsoft

 

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Office Access Help. Help.

The Access Help Task Pane  Pane  will  will  appear  appear  on the right right   side of your screen. When your screen appears, click click-in -in the Search for: area for: area in the Assistance Assistance   portion of the Task Pane. Type-in   ―query Type-in criteria.‖ Then click click-on -on the  ―query criteria.‖ Green Arrow to the right of the Search for: box. Your screen screen   should look similar to the one on the right right..

A Search Results Task Pane will now appear on the right side of your screen (like the one on the right). right ).

Click-on Click -on the Enter criteria to retrieve certain records (MDB). (MDB).

A Microsoft Office Access Help  Help  Menu Screen will appear appear   similar to the one at the top of the next page. page.

When the Microsoft Access Help screen for Enter criteria to retrieve certain

records (MDB) appears, use the elevator bar on  

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the right side of the screen to move to the bottom of the screen.

When you get to the bottom   of the screen, bottom click-on click -on See Also. Also.

A number of bulleted choices will appear. appear. Click-on Click -on Examples of expressions

When the Examples of expressions screen appears, click click-on -on Examples of expressions used in queries and filters.. filters

Your screen will ―expand ―expand‖‖ to a reveal a number of additional choices  choices   (see image at image  at top of next page) page)

 

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One of the new choices will be Examples of criteria to retrieve records. records. Click Click-on -on this selection. Your screen will expand some more, like the image image on  on the left left..

We’ll be using several of these choices in a few minutes. If you would like to see what some of the choices  ―do,‖ click click on them. them.   Choices that we use a lot are: lot are:        

Ranges of values Text, partial , and matching values Dates A blank field‟s value.  value. 

When you are finished finished,, click click--on the ―X ―X‖ in the upper right corner of corner  of the Microsoft Access  Access Help Topics menu screen menu screen to close close the  the screen.

Also, click click--on the ―X ―X‖ in the right hand corner  corner  of the Search Results Task Results Task Pane.

You may return and explore more of these help screens as you become more accomplished with Access 2003 database. These help screens are like having a  

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complete Access 2003 manual on your computer. Now we'll try a few specific queries. queries. First let's find find a  a specific state. state. You should now be back in the Query1: Select Query menu Query menu Design Design   window. It should look like the like the one at the top of the next page. page. If you‟re not  not  then click click   the Design button  button  in the upper left corner of corner  of the screen screen (like  (like the one on the right right). ). Click-in the cell Click-in cell   to the  the  right of Criteria:  Criteria:  in the State State   column. You will see a flashing cursor (Make (Make sure you are in the State column.). column.). Type-in Type-in   the abbreviation   for one of the states you entered  abbreviation entered  in your Personnel Table. Your Query should look like the like the image below. below.

Now click-on click-on   ( !  !   ). A new query window will appear. Only persons from the state you selected   selected should show. This is a SPECIFIC a SPECIFIC query  query for that state state..

Click-on Design View Button (triangle-ruler-pencil)  (triangle-ruler-pencil)  to return to Design View. Now delete the state state you  you entered.

Now we ll look for Favorite Numbers larger than 600. 600 .

Type in  in  >600 in the  the 

Criteria cell under cell under the Favorite Number Column. Click-on Click-on (  ( ! ). Everyone with a favorite number larger than 600 should show. If no one is indicated you indicated you don't  

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have  a person with a number larger than 600, have  600, or you might have typed the >600 incorrectly. Return to  to  the Design View. View. Delete Delete   the the   >600  >600  and run the query with no criteria. criteria. You should ―see see‖‖ all the the   fields fields   again. Return to  to  the Design View again. View again. Make sure all the Criteria: cells are empty. empty . Next we'll look for persons with salaries equal to or larger than $ 20,000 and equal to or less than $ 50,000. 50,000. In the Salary Salary field  field column, in the Criteria: Criteria : cell type-in::  type-in >= 20000 and . The order The order   which you click-on click-on the fields   will be their order  fields order   in the report. The  The   >> brings over all of the fields. fields. The < The  < brings back one of the fields which which you have selected selected and and