NATIONAL ASSOCIATION FOR THE BLIND
Hardware & software concepts explained for persons with low or no vision for the students of Intel Technology Training Lab at National Association for the Blind, New Delhi
Produced and Published by National Association for the Blind Sector-5, R.K Puram, New Delhi
Reprint: February 2005
TABLE OF CONTENTS
Introduction to input-process-output sequence,
What is a computer?, Where do you use Computer?
2.Hardware Components of the Computer:
Input devices, Output devices, Processing Unit, Memory or Storage, Drive letters, Units to Measure Memory
3.Software: System software and application software
4.Important Terms: Files & folders, Mother Board, Ports, Cards, Data Bus
1. INTRODUCING COMPUTER
1.1 Introduction to input-process-output sequence
Any activity has an input-process-output sequence. For example, for preparing milk shake, milk, sugar and flavour are the input. These things are processed in a mixer and the milk shake is the final output.
Example of Human Beings
When the teacher asks the student to ADD 5 & 2. It forms an input to the student. The addition is performed in the brain of the student - process When the result is spoken out by the student, it forms the output
1.2 What is a computer?
Computer is a data processing tool. It takes Data and commands as input. Computer processes the data according to the commands and provides the resulting information as an output.
1.3 Where do you use a computer?
Computers are used at various places for example:
LIBRARIES: Computers are used in the library for producing and maintaining catalogue of the available books. They are also used by the members to search for their topics in the available books. The computers are also used for maintaining the records of the members.
RAILWAYS: Computers are used for reservation of tickets.
AIRPORTS: Computers are used in flying the aeroplanes.
OFFICES: Computers are used in offices to handle the routine office work.
2. HARDWARE COMPONENTS OF A COMPUTER
What is hardware and software?
The physical components of a computer are called the hardware. The component that can be touched will come under hardware. All the electronic, electrical and mechanical parts that make a computer are called the hardware. For example, keyboard, monitor, computer chips, system box, etc are the hardware of the computer.
Software is the set of instructions, which run the hardware of the computer. The hardware components of the computer act according to the instructions. These instructions are called the software. In a story book, paper and the ink are the hardware. The story or the meaning conveyed to the reader is the software. Software is the ingredient that set up a computer to perform a certain operation. Brings the machine to life. Data and instructions form the software.
There are four components of a computer:
1. Input devices
2. Output devices
3. Processing unit
2.1 Input Devices: Input devices are those devices that we use to send information into the computer.
Common input devices are:
A.Keyboard: It is a board with 104 keys on it. These keys are divided into four sections: Number keypad, intermediate keypad, typewriter keys and function keys. In the past the keyboard had only 84 keys. This keyboard did not have the intermediate keypad. There also was a keyboard with 101 keys.
B.Mouse: This is a pointing device. This device fits under the palm of the hand and has two or three buttons. As we move the mouse on the table, the mouse pointer moves on the screen. The pressing of the mouse button is called clicking the mouse button. Clicking a mouse button twice quickly is called double click.
C.Scanner: Scanner sends an image of a page to the...