Basic Computer Science for

Beginners

By

Kingsley Idiagbor, B.Sc(Hons), PGDCs

December 2002

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COMPUTERDEFINITION: Computer is an electronic machine used for processing data, store and produce an output to the userDATA: Data is the raw information that is fed into the computer.Data comes in three forms: letters (like a,b,c..)numerals (such as 1,2,3...) and special characters (e.g. $, @,/ ..)INPUT: Input is the process of feeding data into the computer.OUTPUT: is the processed data that is communicated to the user. The output is also

CATEGORIES OF COMPUTER

There are four major categories of computer:

Microcomputers: These are computer systems

that have the microprocessor in one case.They

are further subdivided into palmtop,

notebook, laptop and desktop computers.

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Input Process Output

Storage

2. Minicomputers: These are more powerful than the

microcomputers and can support a number of users

performing different tasks. Most powerful mini-computers

are called super mini-computers

3. Mainframe: They are large systems that can

handle hundreds of users. They store large amounts

of data and process transactions at high rate.

Mainframes require several rooms to store.

4. Super-computers: They are the most

powerful category of computers and also the most

expensive. They are used for such applications as

weather forecasting, engineering designs and testing,

space exploration and other tasks, which require long

and complex calculations.

TYPES OF COMPUTER

We have three different kinds of computers:

i) Analog computers;

ii) Digital computers and

iii) Hybrid computers

Analog computers

These are devices that measure one form of

physical quantities or another like temperature, pressure,

speed and so on. Examples of analog computers are

thermometer, barometer, speedometer and hygrometer

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Digital computers:These are devices that are used for

counting. Examples include adding machine, billing machine, electronic wrist-watch and calculator

Hybrid computersThese devices combine the functions of

measuring physical quantities as well as counting.

Electronic computers like desktop computers and

notebooks are examples of hybrid computers

PARTS OF A COMPUTERThere are four major parts of a computer:1. Monitor;2. System Unit (which contains the CPU,hard

disks & others)3. Disk drive (provides slot for diskettes)

4. Keyboard

Monitor

System Unit

Disk drive

Keyboard

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PERIPHERALSThese are those external devices that

must be attached to the System unit for them to work.Examples of Peripherals:i) mouse;ii) light pen;iii) printer;iv) plotter;v) modem (modulator-demodulator);vi) UPS (Uninterruptible power supply);vii) scanner;viii)telephone;ix) data projectors;x) microphoneamong several others. Some peripherals, not a major part, are becoming indispensable features of a modern PC (Personal Computer). Examples are the mouse, scanner and printer

HARDWAREThis is the physical component of the computer which we can see and touch

Hardware is made up of four types of devices or units. These include: input devices, processing devices, output devices and storage devices.

INPUT DEVICESInput devices are those devices that are used for feeding in data into the computer.Enlisted below are various input devices:i) keyboardii) mouse;iii) scanner

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iv) light pen;v) joystick (for playing computer games);vi) voice input;vii) touch screens;viii) trackball;PROCESSING DEVICES

These are units that process data from one form to another. The CPU (central processing unit) which is generally regarded as the 'heart' or the 'brain' of the computer, is a major processing device. Another example is the Modem (modulator-Demodulator) which is processes data for communication purpose. The modem enables the computer to dial a telephone or access the INTERNET (more on this later on the course) by dial-up methodOUTPUT DEVICES They are devices that computer uses to produce output (information)or the unit that is used to communicate with the user. They may include:a) monitor;b) printer;c) data projectors;d) plotters;e) computer output microfilm;f) voice output (such as we find in Robot technology)

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STORAGE DEVICESStorage is the fourth and final

operation in the information processing cycle (earlier mentioned). As the name implies, storage devices are those devices used for storing data and programs for later use. We have primary storage (main memory inside the system unit) and the secondary storage devices. The latter is sometimes calledAuxillary storage. In the section that follows, we are going to look at some of them in detail:

MONITORMonitor is the part of the computer that looks like television set. It is variously called as CRT (Cathode Ray tube), VDU (Visual display unit), Screen or just Display.

The output that is displayed on the computer cannot be touched, as it were, and is called soft copy output.Pixel: also called 'picture element’ are the individual dots that make up the text or graphic and can be illuminated. The greater the number of pixels, the better the screen resolution.Resolution: This is the clarity of a monitor and is determined by the number of pixels that can be illuminated.

TYPES OF MONITORSWe have two major kinds of monitors: monochrome monitors and colour monitorsMonochrome Monitors: They are computer terminals that display a single colour such

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as amber, green or white on a black background; or black

characters against white backgroundColour MonitorsThey are more expensive than the monochrome

monitors and are more desirable because

colour enables users to more easily read and

understand the information on the screen.

Several Graphic standards have been developed and they include:CGA: (Colour Graphics Adapter);EGA (Enhanced Graphics Adapter)VGA (Video Graphics Array)SVGA (Super Video Graphics Array)

Each standard provides for a different number of pixels and colours and offer even higher resolution screens.

With the development of mobile

computing in the form of truly portable

computers that could be conveniently carried

by hand or in a briefcase, came a need for an

output display that was equally portable.

Today, we have what we call the Flat panel

Monitors that are actually LCD (stands for

Liquid Crystal Display) and plasma

screens.There are also the TFT (stands for

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thin-film transistors) monitors that makes

use of LED (Light emitting diodes).

Printers

Printers are very important peripheral

in that they produce hard copy output that

the user can carry about unlike the soft copy

output from monitors.

How are Printers Classified?

Printers can be classified by how they

transfer characters from the printer to the

paper. This is either by impact or non-impact

Impact printers

These transfer the image onto the paper by

some type of printing mechanism striking the

paper, ribbon, and character together.

Examples of impact printers include:

a) dot-matrix printer

b) daisy wheel printer

c) chain printer

d) band printer

Non-Impact printers

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There are also a variety of non-impact

printers. These include ink-jet printer,

thermal printer and page printers like the

laser jet printer.

Choosing a Printer

Besides understanding the features and

capabilities of the various types of printers

that are available, one must consider other

factors before choosing a printer. Such

factors include how much output will be

produced, the speed as well as the quality of

the text and graphics. Laser-jet is very

desirable for printing heavily text documents

while ink-jet printer is the best bet for

graphics intensive documents.

Terms associated with Printers

DQ Draft quality

NLQ Near Letter quality

LQ Letter quality

CPS Characters per second

PPM Papers per minute

BRIEF HISTORY OF COMPUTERS

Computing has a long history and started with man’s search for the best method of easy counting and manipulation of items

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and number of materials and other resources. The Chinese and the Ancient Babylonians made use of the Abacus. During the renaissance period however, notable scientists like Blasé Pascal, James-Marie Jacquard, and Charles Babbage devised better counting devices. We had the punched cards by Jacquard, Herman Hollerith’s tabulating machine that eased the 1890 American census and became the older cousin of the IBM computers. The first electronic computer was the ENIAC and was developed by IBM in the year 1946. They were very large and produced large amount of heat because of the use of vacuum tubes. They were the first generation computers. The development of transistors gave birth to the second-generation computers, which were not as large and produced less heat. In 1969, Ted Hoff invented IC (Integrated circuit) and together with Gordon Moore developed the 8008 microprocessor in INTEL. Microcomputers were born. In 1975, average person could now purchase personal computers. In 1980, IBM gave Bill Gates of Microsoft Corporation, a contract to come out with an operating system. His MS-DOS and later several releases of ‘Windows’ have changed the face of computing world-over.

INTERNET is the information superhighway that started as ARPANET in late 60s but became popular in the mid 1990s. With the advent of INTERNET came e-commerce, e-mail, virtual research, and teleconferencing. Suffice it to say that the INTERNET is perhaps the greatest gift of computing to man

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and has changed the way that he views his world.

COMPUTER TIMELINE [summary]

1400 BC Abacus

1800 AD James-Marie JacquardWeaving1 loom machine /cards

Fig: Jacquard’s punched cards

1890 Charles Babbage [generally

regarded as Father of computer]

analytical engine

1890.1924 Herman Hollerith’s

tabulating machine

1937 Atanasoff-Berry-Computer [ABC]

1946 von Neumann & Mauchley –ENIAC

1952 Grace Hopper programs computer

using symbolic code. Note that

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Fig: Charles Babbage’s Analytical Engine

Ada Lovelace, a woman, was the

first programmer

1957 FORTRAN programming language

1958 Computers built with transistors

1969 Ted Hoff of Intel developed a

microprocessor codenamed Intel

4004;

ARPANET-forerunner of INTERNET

1970 4th generation computers

1975 MITS-the first commercial PC

1976 Steve Jobs & Steve Wozniak built

the first Apple ® computer

1980 Bill Gates –MS-DOS

1981 IBM PC introduced

1983 Mitch Kapor –Lotus 1-2-3

1984 Apple introduces Mac computers

1989 Intel 80486 microprocessor for

486 computers

1990 Microsoft released Windows 3.0

1995 Microsoft released Windows 95 w/

FAT-32 addressing system &

Internet browser in one

1995 Pentium technology

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1996 More domain registration for

INTERNET

1997 Nanotechnology & miniaturization

of computers

1998 Microsoft released Windows 98

April 8, 2023

What is a program?

Program is a set of instructions that are

fed into a computer to carry out a task.

The computer is lifeless and you can really

not do any thing without programs. We can type

our letters with the computer because of a program

that makes the computer to allow us to do so. The

program could be a simple one like instructing the

computer to add two numbers together or could be

a complex one like forecasting what the weather

would be like in Calabar tomorrow.

Programming Language

If I want you to do something for me, that is an

instruction, isn’t it? You cannot actually carry out

the instruction if you did not understand my

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language. It is so with the computer, too. To be

able to write a program, the instructions should be

written in a language that the computer can

understand easily. Such a language is called a

programming language.

Examples of programming language

1. BASIC (which stands for Beginners All-

purpose Symbolic Instruction Code)

2. FORTRAN (Formula Translator)

3. COBOL (Common Business Oriented

Language)

4. ADA

5. Pascal

6. C

7. C + + (pronounced C plus plus)

8. HTML (Hyper Text Mark-up Language –

used for web page authoring in the

INTERNET)

9. JAVA

10. ALGOL (Algorithmic Language)

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There are many other languages that can be used

for writing programs. These are just a few of them.

SOFTWARE

Software is the collection of programs in the

computer, which we can see at times but cannot

touch.

Types of software

There are three major types of software, namely:

a) System software;

b) Application software and

c) Utility software

System software

These are programs that control the operations of

any computer. Some of these operations include

starting up the computer (booting), loading,

executing (that is carrying out instructions).

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System software includes operating system and

language translators or what we call compilers.

Some operating systems include:

a) MS-DOS [Microsoft Disk Operating System]

b) WFWG (Windows [3.11] For Work Groups)

c) Windows 95 or 98

d) Windows 2000 Professional

e) Windows ME (Millennium Edition)

f) Windows XP (Windows Experience)

Application software:

These are programs that are designed to carry out

specific tasks for us. Application software is

sometimes referred to as packages. Again, there

are different types of application software namely:

a) Word-processing : This software enables us

to type letters, memos and documents. E.g.

MSWord, WordPerfect, Lotus AmiPro,

WordStar, Write, MultiWrite, Windows

WordPad and so on.

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b) Spreadsheet: We use spreadsheets to

manage tables, prepare financial reports or

calculate scores for an examination report

sheet in the school. E.g. MSExcel, FoxPro,

LOTUS 1-2-3

c) Computer Graphic software: This

makes it possible for the user to manipulate

charts, pictures and several beautiful

designs with the computer. E.g. COREL

DRAW 10, ADOBE PhotoShop, ADOBE

Illustrator, PRINTMASTER Gold Deluxe and

so on.

d) Database: This software allows the user

to enter data such as the names of students

in a school with their ages and classes and

enables the user to retrieve such information

at a later date.

UTILITY SOFTWARE

This software takes care of the management and

the security of the files inside the computer. We

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have Anti-virus packages like Dr Solomon Virus

Scan, McAfee, NDD, Norton Utilities. There are

also utility software that clears up the hard disks of

nonsense files when the disk is nearly full.

Central Processing Unit

This is the main control unit of the computer. It can

be said to be the brain of the computer or the heart

and so on.

Parts of the CPU

The CPU consists of the control unit and the ALU

(which stands for Arithmetic/Logic unit). These two

work together using the program (instructions fed in

by the programmer, you remember) and the data

that are stored in the main memory to perform.

Therefore the parts of the CPU include

a) control unit;

b) ALU and

c) Main memory

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Main Memory

The main memory stores three items. These

include:

a) the operating system e.g. Windows 95/98 or

windows XP that directs and monitors the

activities of the computer equipment;

b) the application software that will direct the

work that is to be done by the user whether

it to type a letter or design a card;

c) the data, which is currently being processed

by the application software

What is Byte?

What is Memory address?

In the main memory, each location is called a byte.

Just as a house on a street has a unique address

that shows the location on the street, each byte in

the main memory of a computer has an address

that indicates its location in memory.

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The number that shows the location of a

byte in memory is called a memory address

Bit: is short form of binary digit. The computer

basically understands only two things 1 and 0. This

in Mathematics is called number base two or binary

scale.

Nibble: 4 bits make up a nibble

Byte: 8 bits make up a byte or

2 nibbles make a byte

1024 bytes equal 1 kilobyte (KB) (However, this is

often abbreviated to 1000 bytes, so we say that

1kB is equal to 1000 bytes instead of 1024 bytes)

The size of main memory is normally measured in

kilobytes. When memory exceeds 1000kB (1

million bytes), it is referred to in megabytes (MB).

1000MB (that is one billion bytes) then it is called

Gigabyte.

Types of memory

1. RAM – This stands for Random Access

Memory. This is volatile in that whenever

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there is a power outage, everything stored in

the memory is wiped off. This is where the

computer stores the program that it loads

during booting (later on this course) and also

the place that the computer temporarily

stores the data that is being fed in, before

you save the work. Saving is the act of

transferring the work that you are doing to

the hard disk where you can retrieve at a

later time.

2. ROM: This stands for read-only

memory. This is made up of all the

instructions that were stored in by the

makers of the computer. These instructions

enable the system (computer is also called

system) to start up or boot, for example.

ROM cannot be altered (changed) or

modified like the RAM.

3. PROM: This stands for programmable

read-only memory. Here, you can be

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allowed to program what you want the

computer to do but once this is done, you

cannot again change anything. Note that it is

only in the PROM that this programming can

be allowed not the ROM.

4. EPROM: This stands for Erasable

Programmable read-only memory

5. EEPROM: This stands for Electronically

Erasable Programmable read-only memory

What is booting?

This is the initial start-up procedure of the

computer. When you put on the computer, it tests

itself and loads the operating system into the main

memory of the computer. When it is doing this, the

computer is not ready for use yet and is said to be

booting.

Cold Booting

This occurs when the computer is switched on with

the plugs correctly wedged into the socket in the

mains. As a general rule, you put on the CPU first

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before the monitor. When you finish with the

computer, i.e. at shutdown, you put off the monitor

first before the CPU.

Warm Booting

Warm booting means to reset the computer. In this

case, one does not have to put off the computer

before switching it on again. To warm boot, three

keys on the keyboard have to be pressed together.

These keys are Control (Ctrl) key, Alternate (Alt)

key and the Delete key (Del)..

It is suggested that using your left hands (for

a right handed person) press CTRL and ALT keys

together, while at the same time you use the right

hand to hit the DEL key. When you do this, you are

warm booting the computer.

AUXILIARY STORAGE DEVICES

These are devices that store data or the output

from the computer for later use.

Generally, we have the rigid and the removable

auxiliary storage devices

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Types of Auxiliary Storage devices

1. Magnetic disk storage ;

2. Magnetic tape ;

3. Optical disks ; e.g. CD-ROM (Compact disk-

read-only memory) ,CD-i(Compact disk-

interactive), CD-R (Compact disk-

recordable) , CD-RW (Compact disk-

rewritable)

4. solid-state devices ;

5. Mass storage devices and

6. Special-purpose storage devices , e.g. smart

cards and optical cards

Of these types of storage devices, we will discuss

only the magnetic disk storage. It is the most widely

used storage medium for all types of computers.

Diskettes

The removable type is called the diskette. Since

they are thin and flexible, they are sometimes

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called floppy disks or simply, floppies. They are

convenient, reliable and inexpensive.

There are two sizes of diskettes: 3½” floppy

disk and 5¼” floppy.

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Care of diskettes

1. They should be prevented from direct

sunlight;

2. Heavy objects should not be placed on top

of diskettes;

3. Do not expose diskettes to hot places or

high temperatures;

4. Avoid touching the magnetic medium with

bare hands;

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5. Do not press the diskettes with your biro pen

or pencil when writing on the label. That

explains why felt pens are recommended.

6. Avoid bringing diskettes close to magnets or

magnetic materials;

7. They should not be brought near dust,

smoke or water

Hard Disks

This type of magnetic disk storage is rigid and is

fixed inside the system unit. Hard disk is

completely sealed and therefore is less prone to

damage. Example is Winchester® disk, Western

Digital® disk, Maxtor® disk and Seagate® disk.

The hard disk itself consists of round metal

platters on which the data are stored and the read-

write head, which is used to access the data that is

sought.

The storage capacity of hard disks is

measured in megabytes and more recently

gigabytes (that is millions and billions of

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characters) of storage. This is just like you have

60-leave or 80-leave notebooks that will store more

notes than the 40-leave notebooks.

We also have removable hard disks

especially in some notebook computers and these

are used to ensure higher security of the stored

data. There are also hard cards. The hard card is a

circuit board that has a hard disk built onto it. They

provide an easy way to expand the storage

capacity of a personal computer

Protecting data stored on a disk

Regardless of whether you are using floppy disk or

hard disks, you must have to protect the data that

you store on the disk from being lost. The disk

storage is re-usable since the stored data may be

overwritten and replaced by new ones. This is

clearly a desirable feature because we are afforded

the privilege of replacing or removing unwanted

files. However, it also poses the problem and

possibility of accidentally removing or replacing the

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file that we wanted to keep. Therefore, to protect

programs and data stored on disks, we may:

a) Write-protect the diskette:

This is done by using the write-protect

notch that is located at the lower side of

the diskette. So, to prevent writing to a

diskette, you will have to move a plastic

cover to open the window. If the write-

protect notch is closed however it means

that the drive can write or copy

something on the diskette. Once again, if

the window is open, the drive will not

write on the diskette or floppy disk.

b) Back-up storage: Another good

way to protect our programs or data

stored on disks is by creating back-up

storage. This simply means creating a

copy of important programs and data on

one diskette to another diskette. The

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diskette is equally a convenient medium

that is used to back up the data stored

on a hard disk of a personal computer.

Today, we now have recordable and

rewritable compact disks that can store

the entire contents of a hard disk as a

back-up storage. This is made possible

by the use of CD-Writers.

COMPUTER VIRUS

A computer virus is a computer code or

program that is capable of replicating itself and

transferring itself from one computer system to

another. Usually, virus can do such things as

change programs or destroy data. They may even

at times format the entire hard disk or blow up a

monitor or disable a printer.

When the host program (that is the program

with the virus) is shared, the virus is spread. As the

host program is copied to friends through diskettes,

the INTERNET, bulletin boards and other usual

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channels, the virus is also copied along. It infects

the software with which it comes in contact.

They are not detected immediately. Some of

them are like time bombs waiting for particular date

to do their havoc. People who copy the host

software are unaware that the virus exist because it

is coded in such a way as to hide from computer

users for weeks or even months. There are over

9000 viruses known and continue to increase by

day and with the advent of the INTERNET even by

the minute. Major kinds of computer virus include

Boot sector viruses (that prevent the computer from

booting properly), anti-CMOS viruses and Trojan

horses.

Examples of computer virus

December 13 Polyboot A eek80 virus

Black Jesus WM.opey97

Howlen Croween B Klein

Jerusalem virus Holy Moses

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To neutralize the codes of the viruses, we use the

antiviruses such as Dr Solomon AntiVirus kit,

Norton AntiVirus, McAfee Virus Scan among

others. Antiviruses have to be regularly updated if

they are to be effective.

HOW TO AVOID COMPUTER VIRUS

These are some techniques to at least minimize

viruses and their damaging effects:

The computer should be warm booted when

switching suspicious programs or

applications.

Write-protect your diskettes when they are

to be inserted into suspicious computer

systems

Always use Antivirus to scan any suspicious

diskettes before opening any file inside

them.

In using the INTERNET and bulletin board

service, open e-mail accounts with servers

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that provide antivirus software that will scan

all incoming mails.

Do not open or download any e-mail

attachments from unknown sources until

they are scanned.

Even when these tips are followed, they cannot be

total guarantee that your system or diskette could

be virus-free when you engage in swapping (that is

copying software). There fore the best method is to

perhaps avoid swapping. Use only registered and

licensed software and avoid tolerating diskettes

from unknown sources from being inserted into

your system.

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NETWORK

When two or more computers are

connected together, they are said to

form a network.

For computers to ‘see’ each other on a

network, they have to follow the same

set of rules, commands or

configurations called protocol

Examples of protocols:

a) FTP File transfer protocol

b) TCP/IP Transfer control

protocol/Internet or

Intranet protocol

c) NetBEUI British standard

protocol

d) WAP Wireless Applications

protocol

e) HTTP hyper text transfer

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protocol.

Types of Network

There are two major kinds of network

based on the geographical distribution

of the computers:

a) Local Area Network (LAN)

and

b) Wide Area Network (WAN)

Local Area Network: This is when the

computers are connected together

within the same area such as building

or campus

Wide Area Network: In this type of

network, computers connected together

are in wide geographical area like

different cities or even countries.

The INTERNET is a good example of WAN.

What is Server?

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What is Client?

Networking is very advantageous

for file sharing as well as

resource sharing.

When computers are networked, you

wouldn’t have to buy separate printers

for each of them. All you have to do

is buy a single printer for all of

them to share. Note that they have to

have the same protocol, which is the

set of rules and regulations governing

the exchange of information between

computers in a network.

Now, a server is the network control

unit that is dedicated to handling the

communicating needs of the other

computers in a network. These other

computers are referred to as clients.

Whatever is to be shared among the

computers in such a network, say, a

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printer has to be connected to the

server. Using LAN, all the computers

and the server can use the printer.

In a network, communication

channels are very essential. Wires and

cables are used, although wireless

systems such as light beams, radio

waves or carrier-connect radio are now

prevalent. VSAT (very small aperture

terminals) has largely improved the

efficiency of Wide Area networks in

both Intranet and INTERNET access.

NETWORK TOPOLOGY

Network topology describes the

configuration or physical layout of

the equipment (such as computers and

peripherals) in a communications

network.

Types

a) star network

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b) bus network

c) ring network

Gateway: is a combination of both

hardware and software that allow users

on one network to access the resources

on a different type of network.

Bridge: is a combination of hardware

and software that is used to connect

similar networks.

Nodes: Devices connected to a

network, such as terminals, printers

or other computers are referred to as

nodes.

Hub: This is a device that connects

all the workstations or client

computers in a network to the server.

We have 9- port, 16-port hubs and so

on.

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ADVANCED ESSAYS

1800 ADJacquard's Punched Cards

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1800 ADJacquard’s Punched Cards In the early 1800s, a French silk weaver called Joseph-Marie Jacquard invented a way of automatically controlling the warp and weft threads on a silk loom by recording patterns of holes in a string of cards. In the years to come, variations on Jacquard’s punched cards would find a variety of uses, including representing the music to be played by automated pianos and the storing of programs for computers

IBM 80-column punched card format. See also:Charles Babbage’s Analytical Engine & Herman Hollerith’s tabulating machines

1890 ADHerman Hollerith's Tabulating Machines

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It is often said that necessity is the mother of invention, and this was certainly true in the case of the American census. Following the population trends established by previous surveys, it was estimated that the census of 1890 would be required to handle data from more than 62 million Americans.

In addition to being prohibitively expensive, the existing system of making tally marks in small squares on rolls of paper and then adding the marks together by hand was extremely time consuming. In fact it was determined that, if the system remained unchanged, there was no chance of collating the data from the 1890 census into any useful form until well after the 1900 census had taken place, by which time the 1890 data would be of little value.

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The solution to this problem was developed during the 1880s by an American inventor called Herman Hollerith, whose idea it was to use Jacquard's punched cards to represent the census data, and to then read and collate this data using an automatic machine. a

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While he was a lecturer at MIT, Hollerith developed a simple prototype which employed cards he punched using a tram conductor's ticket punch, where each card was intended to contain the data associated with a particular individual.

From this prototype, he evolved a mechanism that could read the presence or absence of holes in the cards by using spring-mounted nails that passed through the holes to make electrical connections.

Herman HollerithCopyright (c) 1997. Maxfield & Montrose Interactive Inc.

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Hollerith's final system included an automatic electrical tabulating machine with a large number of clock-like counters that accumulated the results. By means of switches, operators could instruct the machine to examine each card for certain characteristics, such as profession, marital status, number of children, and so on.

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When a card was detected that met the specified criteria, an electrically controlled sorting mechanism could gather those cards into a separate container. Thus, for the first time it was possible to extract information such as the number of engineers living in a particular state who owned their own house and were married with two children. Although this may not tickle your fancy, having this capability was sufficient to drive the statisticians of the time into a frenzy of excitement and data collation.

In addition to solving the census problem, Hollerith's machines proved themselves to be extremely useful for a wide variety of statistical applications, and some of the techniques they used were to be significant in the development of the digital computer. In February 1924, Hollerith's company changed its name to International Business Machines, or IBM. (See also Hollerith's punched cards.)

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These notes are abstracted from the book Bebop BYTES Back(An Unconventional Guide to Computers)  Copyright Information

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