What is Computer ?

A computer is a device that accepts information (in the form of digitalized data) and manipulates it for some result based on a program or sequence of instructions on how the data is to be processed. A programmer is a person who inputs the data into the computer in order to get a desired final result.

Computer is simply a device used to process data. The data being processed are words if you are running a word processor, pictures if you are running a photo editor, or numbers if you are running a spread sheet. The advantage a computer provides is its ability to quickly process information into a more meaningful form. Computers have existed for hundreds of years in mechanical forms. Gears, pulleys, and mechanical devices could be manipulated in such a way as to accurately accomplish mathematical computations. It wasn’t until the beginning of the 20th century that the idea of an electronic computer was discussed, and it took a world war to make it happen.

The basic parts of a computer are as follows:

• Processor: It executes instructions from software and hardware.
• Memory: It is the primary memory for data transfer between the CPU and storage.
• Motherboard: It is the part that connects all other parts or components of a computer.
• Storage Device: It permanently stores the data, e.g., hard drive.
• Input Device: It allows you to communicate with the computer or to input data, e.g., a keyboard.
• Output Device: It enables you to see the output, e.g., monitor.

Computers can be generally classified by size and power as follows:

• Personal computer: A small, single-user computer based on a microprocessor.
• Workstation: A powerful, single-user computer. A workstation is like a personal computer, but it has a
  more powerful microprocessor and, in general, a higher-quality monitor.
• Minicomputer: A multi-user computer capable of supporting up to hundreds of users simultaneously.
• Mainframe: A powerful multi-user computer capable of supporting many hundreds or thousands of users
  simultaneously.
• Supercomputer: An extremely fast computer that can perform hundreds of millions of instructions per
  second.