TABLE OF CONTENTS€¦ · Types of Computers Functions of Computer Introduction to Data and Information Types of Data and Information Main Parts of Computer ... When watching films,

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TABLE OF CONTENTS

A Computer

Identification of Non computer related objects

Identification of computer related objects

Identification of the computer

Uses of Computer I

Uses of Computer II

Uses of Computer in Daily Life

Computers in Workplaces

Definition of computer

Information Technology

Types of Computers

Functions of Computer

Introduction to Data and Information

Types of Data and Information

Main Parts of Computer

Computer Accessories & Peripherals

Branches of Computer

Test

Basic Concept of computer Unit

Input Unit

Processing unit

Storage Unit

Output Unit

Computer Software

Computer Hardware

What is Booting?

Various Types of Computers and Their Functions

Terminologies/ Glossaries

CONCISE COMPUTER

SCIENCE TEXTBOOK

FOR CHILDREN

BOOK ONE

By:

Wole Adedoyin

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A COMPUTER

PERFORMANCE OBJECTIVES

Pupils should be able to:

i. Identify a computer machine;

ii. Identify computer related objects

iii. Identify non computer related objects

iv. Distinguish a computer from other computer

related devices e.g Television, Global

System for Mobile Communications (G.S.M),

Calculator, and Typewriter etc.

IDENTIFICATION OF NON-COMPUTER

RELATED OBJECTS

Computer Is an electronic machine which input

data, process data and display data (output) in a

desired form.

Non computer related objects are those objects

that have no similarity with the computer system or

having nothing to do with the computer system.

Examples: House, Pencil, Box, Book, Basket, Car

etc.

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Definition of Computer

Computer is a machine that processes data into useful

information.

A typewriter, a calculator, thermometer, speedometer or

even voltage meter can be called a computer.

What distinguishes a computer from other information

processing machines are 3 basic functions :

1. A computer is an electronic machine – all its activities

are carried out with current (light)

2. A computer has memory to hold information for future

use

3. A computer is programmable Computer machine can

be coded or programmed to do any operation we tell it

to do.

Information Technology

Information Technology allows the user to extract, save and

exchange information with the help of computers.

I.T is the short form for Information Technology.

It also enables the user to access, retrieve, manipulates and

perform numerous operations by using the computer system.

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IDENTIFICATION OF COMPUTER RELATED

OBJECTS

These objects are similar and related to the

computer system. Some are also performing the

functions of the computer system, like typing letters,

sending and receiving information and performing

calculations. Examples of computer related objects

are:

Calculator:

Calculator is a computing machine used for solving

both simple and complex calculations e.g addition,

subtraction, multiplication, square root and division.

GSM:

G.S.M stands for Global System for Mobile

Communications. For sending and receiving calls

and messages. Also used for uploading (sending)

files and downloading (receiving) files. Some GSM

also allows the user to browse the internet.

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Ipod digital Media players

Stereo System

Typewriter:

It is a computer keyboard like machine used for

typing documents like letters. Typewriter got

different keys on it like a computer keyboard.

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A Manual Typewriter

An Electric Typewriter

Washing Machine

IDENTIFICATION OF THE COMPUTER

1. C.P.U

This is the brain of the computer system. It

processes raw data into a useful information.

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2. Keyboard

For typing data into the computer system.

3. Mouse

For clicking and dragging objects and text

4. Monitor

It displays information on the television like screen

Test

1. Mention 3 non computer related objects

2. Mention 2 computer related objects

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3. What is the function of the keyboard.

PARTS OF COMPUTER

At the end of the topic, pupils should be able to:

i. Name the parts of a computer

ii. Recognize computer parts

PARTS OF A COMPUTER

Monitor:

Is an output device which display information on the screen.

Another name for monitor is VDU – Visual Display Unit.

There are two types of monitors –

i. Monochrome Monitor

Displays white and black objects on the screen

ii. Colour Monitor

Displays colour objects on the screen.

The monitor looks like a television screen. The information

received through the screen is called soft copy.

Keyboard:

For typing data into the computer system. Keyboard looks like

a typewriter. It got different keys on it. The first five letters on

the first section of the keyboard reads QWERTY.

Keyboard is an input unit.

System Unit:

This is the brain of the computer system. It transforms data

into useful information. It looks like a video machine. It got

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buttons like power button, restart button and other device

connectors. System unit is a processing device.

Mouse:

Mouse is an input device used for clicking and dragging text

and objects. The singular of mouse is mouse while the plural

is mice. Mouse also got different buttons on it e.g left clicking

button and right clicking button.

Printer:

It displays the results on printed sheets. The information

received through the printer is called Hardcopy.

There are two types of printers

i. White and black printer

ii. Color printer

White and black Printer

i. White and black printer

Prints only white and black objects.

ii. Colour Printer

Prints only colour objects

Speaker:

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It bring out sound from the computer system. When watching films,

movies or listening to music always connect your computer speakers

to the system unit. The result received through the speaker is called

Voice copy.

Speakers

Test

i. Draw and colour the pictures of the following

parts – pictures of mouse, keyboard and the

monitor.

ii. Write out the functions of the following

computer parts:

a. Mouse

b. Keyboard

c. Printer

d. Monitor

e. System Unit

USES OF COMPUTER I

At the end of this topic

Pupils should be able to state the uses of a computer

Uses of Computer II

At the end of the lesson pupils should be able to mention additional

uses.

Use of computer III

Pupils should be able to mention more uses of the computer in daily

life.

USES OF A COMPUTER

1. Drawing Objects

Computer can be used to draw shapes and objects of different

shapes and sizes. A good artist can use computer to draw a human

being, houses, cars, trees, logos and other artistic drawings. Mouse

is used for drawing while keyboard is sued for labeling on what you

draw.

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2. Playing Games

There are numerous games in the computer – games like car race,

ludo, dice, mortal combat, Mario, soccer and play station can all be

played in the computer system. Users are to make use of either the

keyboard or mouse to control their players and set games options.

3. Typing of Text

Keyboard is used for typing text into the computer system.

Any letter, be it formal, informal or semi-formal letter can be

typed into the computer system through the keyboard. When

typing, computer sometimes proof read or automatically

corrects wrong spelling and vocabularies.

4. Playing Music

Computer is now a modern tool for some notable musicians.

Users are now using their computers to play music, listen to

music and watch different movies.

5. Watching Educational Movies

Some educational films or documentaries which are meant to

educate, entertain and inform users on some subjects or topic

they are hearing for the first time can be played on the

computer system. Some difficult school subjects like Maths,

English etc. are now stored in the CD ROM to be played in the

computer system.

USES OF COMPUTER II

1. Saving typed works

Computer now allow the users to continue working where they

left off. Typesetted works like letters, memo and curriculum

vitae can all be saved in the computer system after typing.

Saving such work means the user is making the work

permanently stored in the computer system.

2. Opening saved work

A saved work can also be re-opened if the user want to

continue where he or she left off.

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3. Learning

This is similar to watching educational films and

documentaries. There are much to learn through the computer

system. People learn everyday and the quest for learning is

rising everyday. Computer is an instrument of great learning.

4. Sending and Receiving Messages

Computers are now used for sending and receiving

information and messages. Messages send through computer

are always fast, reliable and secured.

USES OF COMPUTER IN DAILY LIFE

i. Calculation

People are now using the computer to perform, solve and

simplify simple calculations like addition, subtraction,

multiplication, division and square root. There is an inbuilt

calculator in the computer system used for solving

mathematical problems.

ii. Shopping

Buyers can now buy things they like on the computer through

the internet.

iii. Chatting/Online Communication

People from far distance can be talking at the same time. For

example a person in Nigeria can talk to another person in

Brazil without leaving their individual countries. Internet and

Webcam makes this possible.

Test

Mention 6 uses of computer.

COMPUTER IN WORKPLACES

At the end of the topic pupils should be able to:

i. Name some places where computers are used e.g

home, in the school, in hospital etc.

ii. Identify the uses of computers in the school and

home.

iii. Play simple computer games

PLACES WHERE COMPUTERS ARE FOUND

AT HOME FOR CHILDREN TO:

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i. Play Games

Hundred of games from Arcade to Zega are all in the computer

system. Game playing is an entertainment segment in the system.

Some games are also educative and some teaches morals to children.

ii. Keeping Records

Important records and files are always kept for future uses in the

computer system.

iii. Learn

Latest things are always present in computer through the internet.

Latest information and facts can be search for and stored into the

computer system.

iv. Computer can be used for household accounts, filling and as a

diary for appointments and birthday reminders.

v. It can catalogue records, books and photographs.

vi. With electronic mail, letters and messages can be entered into

your computer and then sent instantly to the receiver’s computer.

vii. With computer, it is possible to sit at home and select library

books.

IN THE SCHOOL FOR:

i. Keeping records of both teachers and pupils:

The man function of computer in the school is for keeping the bio-

data, educational data, marks scored by pupils, the schools’ facts

and other vital information concerning the school, the teachers and

pupils.

ii. Making Time-Table

Computer is the fastest tool for making timetable. There are other

numerous gridlines, tables which can be customized and formatted

to suit the taste of the user.

iii. Processing Texts

Computer has the ability to process text into a useful document.

Text typed into the computer can be sort, retrieve, save and open

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iv. Learning

Programs like Britannica and Encarta Junior Series makes learning

easy and comprehensible.

IN SUPERMARKET FOR:

i. Entering the sale of goods into a computer

ii. Stock taking

iii. Controlling Stock levels

iv. Recording stock

v. Providing the prices of good: In the Supermarket

prices of goods are always stored in the

computer system. To know the price of a product,

the only thing the user need is to type the name of

the product into the computer and the price will

come out.

vi. Updating Account: Money are sometime stored in

the computer. Money realized during the day, can

be stored into the system. When expenditure is

deducted from income in the computer, computer

will automatically give out the remaining

balance.

vii. Providing information on the goods in stock –

Major supermarkets in towns and cities today are

using departmental layout, whereby their shops

will be divided into different departments e.g

jewelry department, hardware department, books

department – where various books are sold.

Information on each department and list of

products in each department with information on

each products will be stored into the computer

system.

A point of sale terminal used in Supermarket

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A dedicated keyboard is useful when limited number of items is sold

Gathering data using a hand-held device in a supermarket

IN HOSPITALS

i. Patient admissions and discharge (including which

beds are available)

ii. Appointments of outpatients

iii. A booking system for scarce resources such as

operating theatres

iv. Purchasing and stock control

v. Keeping record of patients

vi. Carrying out diagnosis

An infant Incubator

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IN OFFICE

i. To produce written letter and documents (text

productions).

ii. To copy or duplicate text

iii. To file the written materials, so that it can be retrieved

when required.

iv. To communicate information, both within the office and

to those outside the office.

IN BANKS

i. Computers are used to process cheques

ii. Computers are used to calculate interests

iii. Computers are used to keep customers’

accounts

iv. Providing customer’s statement of accounts.

v. Making it possible for a customer for

withdraw money from his/her bank account

at any location of his/her bank in the country.

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Questions

i. Mention 4 places where computers are found

ii. Mention 4 uses of computers in school.

FUNCTIONS OF COMPUTER

1. For processing data

2. For playing games

3. For sending information

4. For listening to music

5. For typing

6. For watching videos

7. For designing

8. For Calculation

9. For organizing and sorting data

10. For drawing and painting

CLASSIFICATION OF COMPUTERS BY PURPOSE

Special Purpose:

They perform specific functions. They are permanently programmed

to do a specific job. E.g traffic light controller, Robots.

Asimo Robot

General Purpose:

These are generally programmed to handle various kinds of

work or for solving day to day transactions or operations e.g

Micro-computer (desktop, Laptop and Palmtop or Notebook).

Test

i. Mention 5 places where computers are used.

ii. List 5 functions of the computer system.

INTRODUCTION TO DATA AND INFORMATION

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Information coded for a computer is called data. Data is an

unprocessed information or raw fact. It is coded or

programmed in form of curved and straight lines called letters.

Information on the other hand is a processed data. Data

transformed or reshape in a readable and understandable

form is called an Information.

Information is often shortened or compressed when coded or

programmed as computer data to occupy small memory

space.

TYPES OF DATA

1. Alphabetic Data : A-Z – Yes , O.K, No

2. Numeric Data : 0-9 – 100,500

3. Alpha-numeric Data – Combination of letters and the

figures e.g A-Z and 0-9 – Number 30

Types of information

Written information

Graphical information

Oral information

1. Written information:

Consist of the typesetted documents. Combinations of

letters which form word, combination of words which form

sentences and the combination of sentences which form

paragraphs. Combination of paragraphs form pages.

2. Graphical Information –

This consist of graphical object or image e.g Postals,

certificates, bill boards, handbills etc. are all often used to

convey and send information from one person to another.

3. Oral Information:

When playing music or watching video cds in your

computers at home, always connects your external

speaker to the back panel (the speaker’s port) where you

connect your speaker at the back of the C.P.U. In case of

Laptop, you don’t need to connect your external speaker

because every laptop computers always come with an in-

built sound. Information conveyed through the sound is

called oral information.

Softcopy

Information displayed through the monitor

Hardcopy

Information printed out through the printer.

Features of computer data

1. Computer can be shared

2. Computer data can be stored and erased

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3. computer data can be stored and edited

4. Computer data can be retrieved

5. Computer data occupies less space.

Features of computer information

i. Information is a processed data

ii. Information must be transformed as data before it

can be processed by computers.

iii. Information processing and data processing both

involve input-process-output and might also involve

storage.

MAIN PARTS OF A COMPUTER

There are 4 main parts of the computer system which

include the followings:

1. CPU or System Unit

2. Monitor VDU

3. Mouse

4. Keyboard

These four parts are the essential parts of a computer system.

A computer having this four parts is called A Complete

Computer System. Because it has CPU (the brain), for

transforming data into a useful information, the keyboard for

typing, the mouse for clicking and dragging of text and object

and lastly monitor for viewing the result on the screen. These

four parts are also called the fixed parts or essential parts of a

computer system. They are also known and referred to as

permanent parts.

Other parts of computer which are not essential like, the

mouse, keyboard, monitor and the system unit are printers,

scanners, digital cameral, joystick, lightpen, OCR (optical

Character Reader), MCR (Magnetic character Reader),

Modem etc.

COMPUTER ACCESSORIES AND PERIPHERALS

Computer Accessories are computer components or parts that

are attached to the system unit.

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They are attached to the C.P.U to haste its fastness and

increase its speed and accuracy. Examples of computer

accessories etc.

Computer peripherals are optionally used with the C.P.U e.g

U.P.S which stands for Uninterrupted Power Supply, Digital

Camera etc. All the devices that are not in the CPU are called

Peripherals.

APPLICATION OF COMPUTERS

- Word processing – For typing and creating

document

- Spreadsheet – For performing calculation

- Graphics – For designing

- Data Processing – For sorting , arranging and

adding data.

- Communication – For sending message though

the Internet and Network.

- Desktop Publishing – typesetting and graphics

Test

1. What is data and information

2. List the type of data that we have

3. ___________ , ___________ , ___________ and

________ are the four main parts of the computer

system.

4. What are Computer Accessories and Computer

Peripherals.

5. Mention 3 applications of computer that you know.

BASIC CONCEPTS OF COMPUTER UNITS

Before any data can be transformed into an information. It

must pass through the following units;

1. Input Unit

2. Processing Unit

3. Output Unit

4. Storage Unit

All computers use the same methods for carrying out the

tasks given to them. The computer takes in Data through input

devices, it manipulates the data according to its instructions, it

outputs the result of its processing and it stores data for later

use. These four processes together are known as the

Computing Cycle.

Input :

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Input is the process of entering data into the computer. The

most common device used for input on Micro-computers is the

keyboard. Computer keyboard include many special keys and

function keys used in performing specialized input tasks as

well as the usual typewriter layout and other input devices

include: a mouse, which manipulates a pointer on the

computer screen for giving commands and entering data; a

scanner, which reads graphic images and pages of text and

sends them to the computer; a modem which receives data

over phone lines and several other devices like joystick for

playing games, light pen , OCR, MCR, Microwriter, Scanner,

keyboard, touch screen, roller balls, digitisers, MICR

(Magnetic Ink Character Recognition), Microphone etc.

A Microwriter

Light Pen

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Roller Ball

Joystick

Touch screen

A Digitizer

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An Optical Character Reader

Bar Code Reader

Hand held numeric key pad

Output:

Getting processed out of the computer is the job of output

devices. The computer can display the data on a monitor

screen of which there are several types:

1. Monochrome or White and Black

2. Color

3. Flat Screen or Panel/LCD (Liquid Crystal Display ) in

the case of both the desktop and the laptop computers.

4. CRT (Cathode Ray Tube) In the case of Desktop

Computer.

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You can also send data to a printer or plotter to make a paper

copy, use the modem to send the data over a phone line to

another computer or use any number of specialized output

devices like speaker, digital camera, projector e.t.c.

Processing:

This part transforms data into a useful information. Once the

data is in a computer, it is processed by the processor and its

associated integrated circuit chips. Processors perform all

calculations and manipulations necessary to transform data

into meaningful information. Also with the processor is the

memory, which is used for storing data and programs while

they are being used by the processor.

You have already seen that computers can receive data,

process it and display the results. However, computer can

also store data for future use. The processing is carried out in

the central processing unit (C.P.U) which is the heart and the

brain of any computer.

The C.P.U is made up of:

1. The Control Unit

2. The Memory

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3. The Arithmetic and Logic Unit (A.L.U)

Storage:

This is the process of saving inside and outside the computer

system. The computer system needs stored programs and

data to carry out the processing. Small amounts of data are

stored on Flash Disk, CDROM. These are called Backing

Stores.

Where do you go if you want to keep the data into a

permanent place? That’s what the storage devices are for.

Storage devices hold date permanently in the computer, so

that you can save it and retrieve it later . All computers use

disks to store data magnetically. Each type of disk is used by

its corresponding disk drive to read and write information.

Floppy disks are used for easy, portable storage and built in

Hard Disks are used for more permanent storage of large

amounts of data and programs for fast access.

Test

1. Mention 4 computer units you know

2. List 5 examples of input devices

3. List 4 examples of output devices

4. Differentiate between input and output units

5. CPU is divided into __________, _______ and

_________

COMPUTER SOFTWARE AND HARDWARE

Hardware:

These are the physical, touchable and the moveable part of

the computer. You will often hear people refer to ……. A piece

of hardware ….. or say, that’s a good piece of software!

Hardware is a term used to describe the actual equipment.

The computer is hardware. Look at your school computer

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system. The keyboard, mouse, CPU, joystick, UPS, monitor,

printer, scanner and disk drives are all pieces of hardware.

All computers consist of hardware. They include the computer

itself and all other related physical devices.

COMPUTER SOFTWARE

Software are the instructions that tell the computer what tasks

to perform; data, the information the computer works on and

you, the user, who tell the computer what to do, and for whom

the computer does all.

A program is a group of instructions that tells the processing

device what to do.

Software can be a single program or a set of programs that

work together. Because their meanings are very similar. They

are programmed for solving day to day activities e.g Ms Word,

Ms Excel, Ms paints, Notepad, WordPad, Marvis Beacon etc.

Computer Software

BOOTING

Booting is the process of getting your computer ready for a

particular task or operation.

Types of Booting

1. Cold Booting

2. Warm Booting

COLD BOOTING :

Is the process of getting your computer ready by the power on

button

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WARM BOOTING:

It is the process of restarting your computer system. Or by

using Ctrl + Alt + Del to restart your restart your system.

Various types of computer

1. Thermometer – For measuring temperature

2. Barometer – For measuring Pressure

3. Meter – For measuring voltage

4. Speedometer – For measuring the speed of a car

5. Rain Gauge – For measuring amount of rainfall.

Test:

i. Differentiate between computer hardware and

software.

ii. Define Booting

Terminologies/Glossaries

Booting – The process of getting your computer ready for a

particular task

Software – Programs installed in the computer system

Hardware – The physical part of the computer system

Information – It is a processed data

Data – unprocessed information

CPU – stands for Central Processing Unit – It is the heart and

the brain of the computer system.

Output – Result gotten from the computer system

Softcopy – The result display on the monitor.

Hardcopy – Result printed out through the printer

Input – Process of sending data into the computer

Storage – Process of saving inside and outside the computer

system.

Processing – Process of transforming data into a useful

information.

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ACCESSORIES OF COMPUTER

Mouse

Keyboard

Scanner

Joystick

Light pen

Printer

CPU

Monitor

Peripherals of Computer

Plotter

Digital Camera

UPS

HARDWARE

Mouse

Keyboard

Scanner

Joystick

Lightpen

Printer

CPU

Monitor

Plotter

Digital Camera

UPS

SOFTWARE

Ms Word

Corel Draw

Adobe PageMaker

NotePad

WordPad

Ms Paint

OUTPUT

Plotter

Printer

Digital Camera

Webcam

Monitor

Speaker

INPUT

Mouse

Keyboard

Scanner

Joystick

MICR

MCR

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OCR

Light pen

PROCESSING

CPU

STORAGE

Hard Disk

CD ROM

Floppy Disk

Zip Disk

Flash Disk

CD Writer

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