Computer are work on input and output commands that we give to the computer with some devices that are called input and output devices. Number 1 keyboard. Keyboard is used for entering or feeding data into computer. This is mostly used input device.

It is just like a typewriter with some work is, which help for computer user. Keyboard may be divided into following groups. Alphabet keys, numeric key symbol key , functional key, cursor control key , special key and enter key. Mouse is also used for input data to the computer.

Mouse is a pointing device and use to select different options. It move on a small rubber ball and has two or three button on the top and to use on a flat surface on mouse pad. It is also help to be able to move the pointer quickly around the screen and select the option.

There are many input and output devices like Joy Stick, scanner, microphone and other machinery that are attached to the computer are included into input devices. And output devices that give us the result to the computer are called output devices.

Monitor that display the functions screen, printer that give us the data in the form of paper, speaker that give us data in the form of voice, CD that give a status in the form of copyright disc , hard disc, USB are the example of output devices.