10 Sending and receiving data

10.1 Introduction

A stand-alone computer receives data from a user by means of input devices. The two most commonly used input devices are the keyboard and the mouse. A computer sends data to a user by means of output devices. Data may be output via devices such as a screen or a printer.

There are many different ways of getting data into a computer. For example, a scanner converts images and texts into a format that can be processed by the computer and displayed on screen. Devices such as touch screens and graphics tablets convert the pressure from stylus or finger strokes into data. Data from digital cameras and camcorders can also be received by a computer.

Some devices can be used for a number of purposes; for example a printer, scanner and photocopier can be combined as one physical device.