Ans : A computer is an electronics device. It is Used to calculate, manipulate, store and retrieve the information and data.
We use digital computers. They operate on binary digit 0 and 1. They understand information composed only 0s and 1s. In the case of alphabetic information, the alphabets are coding in binary digits is call bit.
A group of 8 bit is called byte. It does not operate an analog quantities directly. If any analog quantity is to be process, It must be converted into digital quantity before processing. The component which converts alpha-numeric characters to binary format and binary output to alpha-numeric characterizes are the essential parts of the digital computer. but the electronic components which convert analog quantity to digital quantity to analog quantity are connected to a digital computer as peripherals where needed. Processing of analog quantity is usually encountered in industrial control and instrumentation, not in general purpose computation, text manipulation or information storage, retrieval or transmission.
Characteristic of computer:
1. Automatic : An automatic works by itself without human intervention. Computers are automatic machines because once started on a job, they carry out the job without any human assistance.