An input device allows users to communicate and feed instructions and data to computers for processing, display, storage and/or transmission. Examples of input devices include graphics tablets, cameras, video capture hardware, trackballs, barcode readers, digital cameras, gamepads, and joysticks. An output device sends data from a computer to another device or user, with most output meant for humans in the form of audio or video. Examples of output devices include monitors, printers, plotters, projectors, LCD projection panels, computer output microfilm, and speakers. This document was done by G.SRI HARSHA of class IX D.