COMPUTER AND FUNDAMENTALS

Definitions;

Lay man’s definition:

‘A computer is a device that can make work easier and faster than a human being can.’

Technical definition:

A computer is an electronic device, operating under the control of instructions stored in its own memory. These instructions tell the machine what to do.

Thus, ‘the computer is an electronic machine capable of accepting data (input), processing data arithmetically and logically, producing output from the processing, and storing the results for future use’.

Most known computers are desktops, tower, laptops and palm tops. Computers are commonly called “PCs,” or personal computers.*

HISTORY OF COMPUTERS

The first computers were people! True or False? i.e. earlier mechanical computers were given this name because they performed the work that had previously been assigned to people. “Computer” was originally a job title: it was used to describe those human beings (predominantly women) whose job was to perform the repetitive calculations.

The first fully electronic computers, introduced in the 1940s, were huge machines that required teams of people to operate. Compared to those early machines, today’s computers are amazing. Not only are they thousands of times faster, they can fit on your desk, in your lap, or even in your pocket.

EVOLUTION OF COMPUTERS

Evolution of computers describes the gradual changes that computer underwent from ancient time up to date. This gives the explanation of early devices and how they were applied. Thus, early thinkers created a number of devices that were used to supplement the human’s ability to reason.

There are roughly three phases in computer evolution:

1. Early machines:

• Abacus:

It was a computational tool that was used to quickly ADD and SUBTRACT numbers.

It was used in China and Japan for thousands of years.

• Slide Rule:

It was first analog device to perform MULTIPLICATION and DIVISION by adding and subtracting.

It used the same principle of logarithm except it was represented on a scale instead of a table. It was invented in the year 1620 by William Oughted.

• Napier’s Bones:

Used a set of long rods which looked like bones hence the name Napier’s bones. It was used for MATHEMATICAL calculations including MULTIPLICATION and DIVISION. It was designed by Napier in the year 1600.

1. Mechanical Era computers (1623 – 1944)

During this era, machines had moving parts like mechanical gears, electronic relays, dials and most of them used punched cards and tapes.

• Pascal’s Adding Machine:

It was the first mechanical adding machine using a system of gears and wheels. It was developed by Blaise Pascal (Pascal programming language was named after him).

This machine was used to ADD and SUBTRUCT numbers. The user could line up two sets of numbers on two different dials and then turn a crank to operate the system of gears that would bring another set of numbers into view with the correct answer.

• Jacquard Loom:

It used punched cards as well. It was developed by the French inventor to automate rug weaving on a loom in 1804. The device used holes punched in cards to determine the setting for the loom. This technology eliminated jobs that had been done by humans for centuries.

• Difference Engine:

These were efforts of Charles Babbage who realized that time consuming mathematical tasks such as calculating the squares of numbers which required systematic approach that could be automated. He invented 1^st programming machine in 1936.

• Census Tabulation Machine:

40 years later after invention of Jacquard Loom, Dr. Herman Hollerith put Jacquard’s punched card concept together with the tabulating machine.

Later he formed the tabulating machine company which merged into an organization that would grow and evolve into International Business Machine (IBM) Company.

1. Modern computers:

In this phase, computers have big memory which leads to high speed. They also perform many tasks at once.

Computer’s specifications:

• Processor (Measured in Hertz (Hz).).
• Memory (RAM) – Measured in Bytes
• System Type – Measured in bits (16, 32, 64 or 86 bit operating system).

COMPUTER CLASSIFICATION BY GENERATIONS

This is the advancement of computer technologies over years. Each computer technology is characterized by dramatic improvement over the previous technology used to build the computers, the internal organization of the computer and the programming used.  With each major breakthrough, the computers based upon older form of electronics have been replaced by a new generation of computers base upon the newer form of electronic.

Thus, generation describes the grouping of computers according to their characteristics in relation to history.

There are basically 5 generations of computers. Namely;

1. First Generation (Vacuum tubes)

Most of the computers invented in this period used vacuum tubes.

Characteristics:

• Large –room sized computers
• Used thousands of vacuum tubes for internal operations
• Not reliable because of their design which relied on radio tubes
• Consumed a lot of power
• Generated a lot of heat
• Had many wires
• Had limited primary memory hence low speed
• Used punched cards for input and output; introduction of high programming language e.g. FOTRNT by John Backus.
• Computers were too expensive.

Examples include

• Mark; 1944 (Automatic Sequence Controlled Calculator)
• Atansoff – Berry Computer (ABC)
• Electronic Numeric Integrator and Calculator (ENIC); (1946)
• Electronic Discrete Automatic Computer (EDAC); (1946)
• Universal Automatic Computer (UNIVAC)
• 701 and 752 Computer as well as FORTRN Programming language by IBM

1. Second Generation (Transistors)

Unlike the first generation computers, these used transistors for internal operations and typically contained 10,000 transistors hand soldered and connected by wires and they were reliable.

Characteristics:

• Introduction of high level programming language like COBOL
• Computers become less expensive than the 1^st
• Computers gave off less heat, small in size, processing speed increased and became more reliable than the 1^st

1. Examples include

• Introduction of high Level language (COBOL) – Livermore Automatic Research Computer (LARC)
• Tele-Star Computer; – for American airline

1. Third Generation (Integrated Circuits – IC’s)

In this generation, Integrated Circuits were usable.

Characteristics:

• Introduction of integrated circuits semiconductors devices with several transistors built into one physical component.
• Use of parallel processing
• Introduction of operating system e.g. Multics
• Low cost of computer
• Highly reliable and small in size in comparison to 1^st and 2^nd
• Consumed less heat than 1^st and 2^nd

Examples include

• IBM 360 – 1964
• DEC – PDP-8 mini computers – 1965
• PASCAL Programming Language

1. Fourth Generation (Large Integrated Circuits – LIC’s)

These are computers in use today which contain more sophisticated microelectronic devices such as complex IC’s or large scale integrated circuits.

Characteristics:

• Development of the microprocessor
• Computers are more powerful
• Cheap enough for purchase

Examples include:

• Micro-computers IBM – 1979
• PC – 1981
• Laptop – 1988

1. Fifth generation (Very large Integrated Circuits – VLIC):

There are many predictions that in a few years to come, computers that will be able to converse with people in human like manner and will be able to mimique human senses, manual skills and intelligence.

Artificial intelligence methods give computers the capability to make decisions based on evidence of the past rather than on a set of programmed procedures. Thus, thinking like human beings.

Characteristics:

• Artificial intelligence
• Mimique human senses

Examples include

• Robotics machines
• Weather forecasting machines.

COMPUTER CLASSIFICATION BY SIZE/CAPACITY

Classification by size / capacity – Examples includes Main frames, mini computers, microcomputers (Personal computers-PC)

COMPUTER CLASSIFICATION BY FUNCTION/PROCESS

Classification by function (process) – Examples includes analogue, digital and hybrid computer

COMPUTER CLASSIFICATION BY PURPOSE

Classification by purpose – Examples includes Special and general computers

COMPUTER CLASSIFICATION BY POWER

Classification by power – E.g. Supercomputers, Workstation computers, Weather forecasting

computers etc.

CHARACTERISTICS OF COMPUTER

• SPEED: In general, no human being can compete to solving the complex computation, faster than computer.

• ACCURACY: Since Computer is programmed, so whatever input we give it gives result with accurately.

• STORAGE: Computer can store mass storage of data with appropriate format.

• DILIGENCE: Computer can work for hours without any break and creating error.

• VERSATILITY: We can use computer to perform completely different type of work at the same time.

• POWER OF REMEMBERING: It can remember data for us.

• NO IQ: Computer does not work without instruction.

• NO FEELING: Computer does not have emotions, knowledge, experience and feeling.

PARTS OF A COMPUTER (COMPONENTS OF COMPUTER)

A computer is made up of a collection of different components that are interconnected together in order to function as a single entity. This includes:

1. Hardware
2. Software
3. Live ware / human ware / computer operator
4. Data and Information

1. LIVE WARE

These include the computer users. i.e. ‘you’ and ‘me’.

Other operators include computer analysts, designers, programmers, network operators etc.

These people put computer in use according to their needs.

1. HARDWARE

These are the physical components of a computer, i.e. can be seen and touched.

CATEGORIES OF COMPUTER HARDWARE:

1. Input devices

These include hardware through which data is entered in the computer. They convert human language into computer ‘binary’-(0’s & 1’s) language.

Examples of input devices include:

1. Keyboard – the keyboard is used to enter text data (i.e. characters e.g. a, b, x, *, +, #, 7 etc.) and instructions into the computer system. It has a layout of keys which represent different characters.

1. Mouse – the mouse is mostly used to give instructions to the computer system, with limited data input capabilities. It’s used to control and select items in the computer by means of a pointer.

1. Scanner – this is used to acquire images into the computer system. The process of storing an image into the computer is called scanning

1. Others – other examples include light-pens, touch screens, microphones, webcams etc

1. Output devices    

These are devices through which the processed data or information is availed to the user. They convert machine language into a human understanding language.

• Output refers to the feedback that we get from a computer system. This can be data, information instructions etc.

            Data & Information

• Data is a term used to refer to unprocessed facts. We can call them raw facts/un-organized facts etc
• Information is a term used to refer to processed facts. We can say information is the ‘result of data processing’ or ‘organized facts’.

• Examples of output devices are:

1. Monitor – a monitor provides screen output from the computer. It displays what the computer is doing and to view output before being sent to other devices e.g. printers. Screen output is called soft-copy. This is because it cannot be used without or away from the computer. There are two types of monitors: a) CRT (cathode ray tube) which are the normal monitors and b) LCD (Liquid Crystal Displays) we call them ‘Flat Screens’

1. Printers – printers are used to get output on paper. Printed papers are called hard-copy output since you use them away from or without the computer. There are several types of printers namely Dot Matrix printers, Ink Jets, Laser printers etc. The type of printer determines the speed at which it can print. Dot matrix is the slowest while the Lasers are the fastest.
2. Speakers – these are connected to the computer to get sound, just like any other speakers.
3. Plotters – plotters are for drawing large diagrams using computers. They are mainly useful in engineering drawings like printing plans, designs, charts etc.
4. Others – there are many other output devices that can be connected to the computer e.g. Projectors

• Hardcopy:- this refers to the tangible information produced on

papers through the printer

• Softcopy:-  this refers to intangible information displayed on the screen.

1. Processing / System unit (CPU)

This is the part that holds / houses the ‘brain’ of a computer. Some of the hardware devices in the system unit include;

1. 1. The CPU, commonly known as the processor,(microprocessor)  is the one that carries out actual data processing in the computer. It is mounted on a motherboard. All instructions and data manipulations take place here. The CPU is made of a micro-chip device.
   2. It controls all other hardware devices in the computer system. E.g signaling a device to start or stop performing a certain job
   3. The speed of the CPU is measured in cycles per second (frequency). The units are Hz (Hertz). 1 Hz is equivalent to 1 cycle/second. Typical processor speeds range from a few MHz (Mega Hertz) to several GHz (Giga Hertz).
      1000 Hz   = 1 KHz (Kilo Hertz)
      1000 KHz = 1 MHz (Mega Hertz)
      1000 MHz = 1 GHz (Giga Hertz)

     iv Motherboard – It is a circuitry center piece on which most/ almost all computer parts are attached to.   This is the part that mounts all the other parts of a computer. Examples of the hardware parts attached to it include microprocessor, communication bus, interfaces and controllers, BIOS CHIP etc.

                v Storage devices – it comprises of ROM and RAM (primary     storage)

1. Storage Devices
   • These are devices used to store data/information/programs in a computer system.
   • Storage devices can be categorized into Internal & External storage devices.
   • The major types of storage include:
     1. Primary storage (Main Memory)
     2. Secondary storage (Disk, Tape etc)

Primary Storage

• This is also called the main memory or as RAM (Random Access Memory). It is also commonly referred to as ‘memory’.
• It is divided into small storage locations which are given addresses. These locations are accessed for data storage by the CPU at random, hence the term random access.
• The memory works directly with the CPU and therefore this makes it very fast compared to other types of storage.
• It uses circuits to store data. This makes it depend on constant supply of electricity in order to work. If power goes off, or the computer is switched of, all that is stored in the computer’s memory is lost. This is referred to as being

How does the computer store data in Memory?

• A computer recognizes data in only two forms, either 0 or 1. This is referred to as binary form, which means 2. Each of the 0 or 1 is called a Characters are represented by unique combinations bits (0’s and 1’s). These combinations are internationally standardized for computer systems.

Secondary Storage

• Secondary storage devices store data/information permanently. They can be internal or external.

• An internal storage device is not portable, or rather, it is not meant to be used for transferring data between computers. It is meant to be used with only one computer system, and can only be moved to another computer by some changes in the computer and device settings.

• An external storage device is portable. i.e. it can be moved from one computer to another without difficulty. They are meant to transfer data and programs between computer systems. E.g. Floppy disks, flash disks, CD’s, hard disks etc.

1. Communication hardware

These devices transfer data and information from one computer component to another.

They also link peripheral devices to system unit.

Examples include; communication cables, modems, communication buses etc.

LOGICAL STRUCTURE OF COMPUTER

System unit (CPU)

1. COMPUTER SOFTWARE

• Software is programs / instructions / applications within the computer system control and manage the computer’s operations.
• Programs are meant to perform/execute different types of tasks within the computer.
• There are three major categories of software:
  1. Systems Software
  2. Applications Software

• Programming Software

1. Systems Software

Systems software are programs that manage and control the computer system

They manage computer hardware and control other software programs installed in the computer.

They also control and manage how users access and work with the computer system.

Examples of systems software include:

            Operating Systems (OS)

• An O/S is the most important component of systems software. It is the one that manages all the hardware and software in the computer system.
• It starts and stops hardware devices during task executions, allocates jobs to the devices and coordinates all hardware and software.
• It determines which programs can be used in your computer and which devices can be connected to the system
• It is usually referred to as the platform since all programs depend on the O/S, and dictates which devices can be used with the computer. Examples include: DOS, Windows family like 95/ NT/98/2000/XP/ Windows 7, Vista, LINUX, etc.

1. Applications Software

Applications are programs that perform individual user tasks in the computer system. They allow the user to achieve his /her need. We can refer to them as the tools that we use to do our work in the computer

There are different types of applications software as shown bellow;

1. Word processing applications:

This are programs used to create office documents e.g. reports, letters etc.

Examples of word processors are;
* Microsoft Word

*Word pad

*Lotus Word Pro
* Word perfect etc.

1. Spreadsheets applications

• These are used for tasks that require a lot of calculations and number manipulations e.g. accounting work
• The spreadsheet applications have a rows and columns layout similar to a ledger book, where data entries are made
• Examples of spreadsheet applications include:
  * Microsoft Excel
  * Lotus 123 etc

1. Presentations applications

• These are used to create visual aids for presentations, e.g seminars, talks, project presentations etc.
• Examples of presentations:
  * Microsoft PowerPoint

*Lotus Freelance

1. Database Applications

*Microsoft Access

*Lotus Approach

1. Payroll Applications

*Sage software

1. Desktop Publishing Applications

*Adobe Photoshop

1. Multimedia Applications:

These contain special hardware that allows you to playback sounds and video pictures. You can then use multimedia software education programs such as games and educational programs.

Examples:  

*Microsoft Encarta CD-ROM based encyclopedias.

1. Web authoring Applications

*Microsoft FrontPage

1. Graphic software

These programs are used to produce high quality graphic. Mostly used by the architectures and designers.

Examples:

*Harvard graphics

*Corel draw

*CAD, Auto CAD

*Auto shop etc.

III Programming Software

These are applications or programmes that assist or facilitate software developers or programmers to do their work. e.g. Compilers, debuggers, Linkers etc. This programming software works in programming languages like JAVA, C++, C, Visual Basic, etc. of which each programming language has its special codes.

OPERATING SYSTEMS

Software that performs computer basic functions such as scheduling tasks, executing applications and controlling peripherals.

Operating System is a suite of programs that has taken over many of the functions once performed by human operators. Its role is that of resource management and such resources may include processors, I/O devices, programs, storage and data.

Functions of OS:

• Scheduling and loading of programs in order to provide a continuous sequence of processing or to provide appropriate responses to events.
• Control over hardware resources
• Protecting hardware, software and data from improper use
• Calling into main storage programs and subroutines as and when required
• Passing of control from one job to another under a system of priority
• Provision of error correction routines
• Furnishing a complete record of all that happens
• Communication with the computer operator.

Types of Operating Systems:

• Single-program systems i.e. are single-user, single-program on small microcomputer-based systems e.g. MS-DOS
• Simple batch systems – provide multiprogramming of batch programs but have few facilities for interaction of multi-access
• Multi-access and Time-sharing – majority of OS fall into this category
• Real-time systems – examples include process control systems.

Methods of operation and modes of access

1. Multiprocessing – where two or more processors are present in a computer and are sharing some or all of the computer memory.
2. Multiprogramming – when more than one program in main memory are being processed apparently at the same time
3. Batch processing – the job is not processed until fully put
4. Remote job entry – batch processing where jobs are entered at a terminal remote from the computer and transmitted into the computer
5. Interactive computing – if the computer and terminal user can communicate with each other
6. Conversational mode – where the response to the user message is immediate
7. Multi-access – if the computer allows interactive facilities to more than one user at a time
8. Timesharing – processor time is divide into small units and shared in turn between users
9. Real time system – capable of processing data quickly such that the results are available to influence the activity currently taking place.

NETWORKS

A network is a collection of computers and related devices, connected so that they can communicate with each other and share information, software, peripheral devices, and/or processing power.

Classification of networks

• Local Area Network or LAN
• Metropolitan Area Network or MAN
• Wide Area Network or WAN

LAN covers a small region of space, typically a single building. Maximum network coverage is about 3 km and is characterized by high speed data transmission

MAN is a collection of LANs within the same geographical area, for instance a city. It enables network coverage of 10 t0 16 miles.

WAN is a long distance network: it connects systems together throughout a country or even beyond the border. It is characterized by low data rates and hardware and software components come from a wide variety of vendors.

Uses of a Computer Network.

• Networks increase efficiency and reduce costs.
• Computer networks achieve these goals in three primary ways:

1. Sharing information: (i.e. documents and E-mail messages)
2. Sharing hardware
3. Sharing software
4. Centralizing administration and support

Selecting the Right Network Type

The type of network you choose to implement will depend on factors such as the:

1. Size of the organization.
2. Level of security required.
3. Type of business.
4. Level of administrative support available.
5. Amount of network traffic.
6. Needs of the network users.
7. Network budget.

The internet

It’s the biggest computer network in the world which links smaller networks worldwide. It doesn’t belong to any particular organization. Internet is the worldwide, publicly accessible network of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol (IP).

Intranet

Is a LAN which has facilities e.g. email within a particular combination but those resources cannot be retrieved from outside the organization.

Extranet

A network belonging to a particular organization and has connection to the outside world therefore users from outside world can retrieve information from outside.

Network topology

Topology refers to the layout of connected devices on a network. Network topologies are categorized into the following basic types:

• bus , ring , star , tree , Mesh,

PROGRAMMING

Programming is the act of developing programs/software that guides and control the operation of the computer system.

A program is asset of instruction written in a well defined order that control the operation of a computer system (should be written in a given programming language.) Programs are written by programmers using programming tools called programming language. Programmers are people who develop computer programs.

A programming language is a special kind of software that is used for building other software. They are generally referred to as developed software’s.

TYPES OF PROGRAMMING

I Procedural programming can sometimes be used as a synonym for imperative programming (specifying the steps the program must take to reach the desired state), but can also refer to a programming paradigm, derived from structured programming, based upon the concept of the procedure call.

Procedural programming is fine for small projects. It is the most natural way to tell a computer what to do, and the computer processor’s own language, machine code, is procedural, so the translation of the procedural high-level language into machine code is straightforward and efficient. What is more, procedural programming has a built-in way of splitting big lists of instructions into smaller lists: the function.

Among the early (first) procedural programming languages like FORTRAN, COBOL, BASIC etc were hard to deal with i.e. they used GO TO statements.

• Example:
• 10 READ A, B, C
• 20 SUM: = A+B+C
• 30 PRINT SUM
• 40 GO TO 10
• DATA

II Structural programming

Structured programming is a programming paradigm aimed on improving the clarity, quality, and development time of a computer program. At a low level, structured programs are often composed of simple, hierarchical program flow structures. These are sequence, selection, and repetition:

III Object-oriented programming (OOP) is a programming paradigm using “objects” – data structures consisting of data fields and methods together with their interactions – to design applications and computer programs. Programming techniques may include features such as data abstraction, encapsulation, messaging, modularity, polymorphism, and inheritance. Many modern programming languages now support OOP, at least as an option.

In 1967, Simula 67 was introduced to handle the limitations of structured programming languages. E.g.

• Small task 80’s
• C++
• JAVA

ALGORITHM

An algorithm refers to a number of logical steps that a program follows in order to solve a problem. An algorithm is developed after the careful analysis of requirement specification.

*Flow charts/Data Flow Diagram

FLOW CHARTS/DATA FLOW DIAGRAM (DFD)

Flowchart is a diagrammatic representation of an algorithm. It is helpful in writing program or a procedure and explaining it in a simpler manner.

• Makes use of a structured methodology toward systems development through the use of data flow, logical data, and entity event modeling.

Symbols used in Flowcharts

Advantages of using Flowcharts

1. Communication: A flowchart can be used as a better way of communication of the logic of a system and steps involve in the solution, to all concerned particularly to the client of system.
2. Effective analysis: A flowchart of a problem is always to the point.
3. Documentation of program/System: Flowcharts are used for various purposes like knowing the components in the program, complexity of the program among others.
4. Efficient program maintenance: It is easy to maintain a program using flowcharts.
5. Coding of program: It is easy to solve a coding problem using flowcharts due to easy conversion from design to computer program.

HOME WORK:

Give the flow charts of the following expressions;

1. If (a>b) then output a

else if (c>d) output will be c

output k;

1. If (a>b) and (c<d) then S1

If (b>d) or (c>a) then S2

S3

• Input student number

Input Hostel number

If student number is OK then check Hostel number

If Hostel number is OK then create room record

Else error 2

Else error 1

FINISH

COMPUTER VIRUS

Virus: – “Vital Information Resource under Siege”

These are computer programs that interfere with normal computer documents. They interfere with the files by deleting, multiplying or sometimes causing the computer to crash. They can be able to copy themselves in the computer memory without the user knowledge.

Source/ cause:

• Network like internet
• Sharing infected / contaminated secondary storage devices
• Fake games
• Illegal computer programs

Symptoms of Virus infection:

• The computer repeatedly tells you that you have performed an illegal operation and the computer has to shut down
• A message that you don’t have enough memory to run or load a program that was previously running well.
• The computer keeps hanging
• Program access takes longer than usual
• Machine takes long to boot
• Files names being changed to code and transferred to a folder called recycled
• Files change sizes unusually and filling your storage media
• Hanging of computer: – a computer may hang while running a program. This might be caused by the user if he/she instructs the computer to carry out so many programs at the same time. We trouble shoot this problem by pressing CTR+ALT+DEL key pads.

This command helps end task that has caused the computer to hang. If the command fails to work, then restart the computer.

Examples of virus:

*computer worms

*Trojan.

*Boot sector

*File virus

*Hoax etc

NB: Dust and moist (vapor) can also interfere with computer’s operation.

Prevention:

• Use of anti-virus software like AVG, A vast, MacAfee, Norton, DR Solomon etc
• Scanning files from the Internet (downloads)
• Avoid sharing secondary storage devices
• Avoid dust and have enough aeration in computer laboratory or computer room.

Scanning the HARD DISK:

If you suspect the hard disk infected and the installed anti-virus cannot work; then, know that any diskette used in the machine will be infected.

To remove the virus infection;

*Boot the machine from a clean write protected system disk;

*Load from a clean diskette that contains the programs. Sometimes the same program disk can act as a boot diskette;

*Select the hard disk (drive C) using the space bar;

*Follow the same procedure as for scanning and cleaning a hard disk.

THE INTERNET

• This is a global network of computers i.e. has no ownership, but is controlled by central bodies. It is simply referred to as WWW (World Wide Web).
• The initial aim of the internet was to access, share or distribute information globally. However, the applications of the internet have gone beyond that. The internet is now an entertainment place, you can do business on-line, learn on-line, etc.
• To connect/publish information on the internet, you need:
  i) Computer (other gadgets can also connect to the internet e.g (a mobile phone).
  ii) Connection – e.g. a telephone line (called Dial-Ups), ISDN (Integrated services Digital network), radio etc. This is provided by a telecom service provider
  iii) Internet Account – Provided by an ISP (Internet Service Provider).

This is basically a username or A/C that you use to access the internet.
iv) Web Browser – Application that reads/accesses internet pages.

E.g.; internet explorer, Mozilla Firefox
v)  And of course some money to pay these people (ISP & telecom)

EMAIL (Electronic-Mail)

These are text messages sent and received through the internet

How do I get e-mail services?
* To be able to use this services, you need to subscribe to an email service provider e.g. Yahoo!, MSN, Gmail etc.
* you will be given an e-mail account which you will use to access and manage your mails
* if your company/organization uses e-mails you can be provided with an e-mail account.

• An e-mail address is of the form:
  your_email_id@your_domain e.g.
  levynyamu@yahoo.com
  The email ID is ‘levynyamu’ and the DOMAIN is ‘com’

SEARCH ENGINES

To search in the Internet, you use what are called Internet search engines. These are easily accessed via your Internet browser. (i.e. Microsoft Internet Explorer, Netscape Navigator/Communication, Opera, Mozilla Firefox etc).

Within the search engine, you enter a word or phrase and it will retrieve documents from the Internet based on the information you typed in.

Examples of International search engines;

• Alta Vista – http://www.altavista.com
• Google – http://www.google.com
• HotBot – http://www.hotbot.com
• Lycos – http://www.lycos.com
• MSN Internet Search – http://search.msn.com
• Yahoo – http://www.yahoo.com

UK specific search engine examples:

• The UK Index – http://wwwukindex.co.uk/uksearch.html
• UK Plus – http://www.ukplus.co.uk
• Yell – UK Yellow Page – http://www.yell.co.uk
• O.D. a UK Search Engine http://www.god.co.uk
• Lycos UK http://www.lycos.co.uk

PROGRAMS INSTALATION

This simply means putting or allowing the instructions or applications in the computer. It is a process of allowing software in the hardware or to (complement) with the hardware.

The process is done by inserting secondary storage device on which the programs are through the required drive then following the procedures respectively as it will be directed by the software to be installed.

ADVANTAGES OF USING COMPUTER

1. Speed – can process work within a short time that could be done by so many people and therefore it is time saving
2. Accuracy – the way you type in data is the way it appears
3. Storage – it can store a large chunk of information in a limited space
4. Secrecy – information is fairly protected if the computer is well managed
5. Reference – one can store documents for future use
6. Security – information can be safely from being accessed by the unauthorized personnel through the use of password
7. Improved customer relations – when you advertise on the internet you do not appear physically but by your writing and thus you can convince customers by writing a good message.
8. Quality of presentation – work in a computer can be presented in various ways and can as well be transmitted easily. Also font style are readable than our own writings. It is educative in that it contains a lot of information and while using the internet one can be updated with the data that he/she wants worldwide.
9. It can be used as an entertainment tool – i.e. one can view movies, listen to music and play games
10. It has a higher memory compared to human beings.

DISADVANTAGES

1. Unemployment – only the skilled continues with job. It does work that could be instead done by many people manually.
2. Cost – the cost of running a computer or any associated information system is high especially to small business operators
3. Health hazard – can cause eye and or with backbone problem
4. Virus attack – this may cause the loss of vital information stored in computer at any time
5. Computers need experts for maintenance which is expensive to hire
6. Loss of information if not well managed is easy.

APLLICATION OF COMPUTER

Computers are used virtually every day and everywhere

1. In institutions – used in teaching and learning process
2. Offices – data management

• Hospitals – monitoring patients and records management

1. Airports – aircrafts management
2. Factories / industries – driving machines and car assembles (robots)
3. Supermarkets – stock control

• Banks – deposits, withdrawals, balances etc. e.g. automated teller machines (ATM’s)
• Transport – monitoring vehicle traffic on a busy town , aircraft navigation etc

1. Communication – message transmission from one person to another efficiently and effectively
2. Law enforcement agencies – information held in computers such as fingerprints, photographs and other identification details helps law enforcers to carry out criminal investigations speedily
3. Domestic and entertainment – computers can be used for recreational activities such as watching movies, playing music and computer games

• Library services – in computerized library, a computer enables library personnel to easily access and keep update records of books and other library materials. Library users can also use computers to search for titles instead of using manual cards catalog.
• Defense and security

COURSEWORK

• Describe the importance of computer in your area of study.
• How can computer applications (Introduction to Microsoft Office) be applicable in your area of study?

NOTE:

            * Use of examples will earn you an extra mark

            * Avoid copy and paste and or photocopying or copying your friends work.

                PENALTY, is that EARNING ZERO (0) mark

            * The work should be WELL researched, properly (if possible individually

                typed) and printed.