Introduction to Computer

 By ABDUL TOMA

What is a computer? (Parts and Functions)

Introduction

In today’s world, computers are everywhere — in schools, offices, banks, hospitals, and even in our homes. But what exactly is a computer?

In this lesson, you will learn:

• What a computer is

• The main parts of a computer

• The functions of each part

What is a computer?

A computer is an electronic machine that receives data, processes it, stores it, and produces information as output.

In simple words:
A computer takes input → processes it → gives output.

Example:

• You type numbers into a calculator (input).

• The computer calculates the answer (process).

• The result appears on the screen (output).

Basic Functions of a Computer

A computer performs four main functions:

1. Input – It receives data.

2. Processing – It works on the data.

3. Storage – It saves the data.

4. Output – It shows the result.

This is called the IPOS cycle:
Input → Process → Output → Storage

Main Parts of a Computer

A computer has two major parts:

1. Hardware

2. Software

1. Hardware (Physical Parts You Can Touch)

Hardware refers to all the physical parts of a computer.

a) Monitor

• Looks like a television screen.

• Displays information.

• It is an output device.

Function: Shows text, images, and videos.

b) Keyboard

• Used to type letters, numbers, and symbols.

• It is an input device.

Function: Allows users to enter data into the computer.

c) Mouse

• A pointing device.

• Used to click, select, and open files.

• It is an input device.

Function: Helps you control the pointer on the screen.

d) System Unit (CPU Case)

This is the main part of the computer.

Inside it, we have:

i) CPU (Central Processing Unit)

• Known as the “brain” of the computer.

Function: Processes all instructions and calculations.

ii) RAM (Random Access Memory)

• Temporary memory.

Function: Stores data while the computer is working.

iii) Hard Drive

• Permanent storage.

Function: Stores files, software, and documents.

e) Printer

• Prints documents on paper.

• It is an output device.

Function: Produces hard copies.

2. Software (Programs You Cannot Touch)

Software refers to programs that tell the computer what to do.

Examples:

• Microsoft Word

• Excel

• Google Chrome

• Windows Operating System

Without software, hardware cannot function.

Types of Computers

1. Desktop Computer – Used in offices and schools.

2. Laptop – Portable computer.

3. Tablet – Touchscreen device.

4. Smartphone – Small computer in your pocket.

Summary

A computer is an electronic machine that receives input, processes it, stores it, and produces output.

Main parts include:

• Monitor

• Keyboard

• Mouse

• System Unit (CPU, RAM, Hard Drive)

• Printer

Computers are important because they make work faster, easier, and more accurate.

Practice Questions

1. What is a computer?

2. List the four basic functions of a computer.

3. What is the function of the CPU?

4. Mention three input devices.

5. What is the difference between hardware and software?