A peripheral driver is the part of an electronic circuit that contains a piece of software that enables a computer to communicate like a transceiver with a peripheral device. Peripheral devices include external computing equipment such as a mouse, keyboard, monitor, printer or scanner.
The electronic circuit connects to the computer to enable the two to communicate with an external (peripheral) device. For example, once a printer or a mouse is connected to a computer, a connection is created, allowing the user to print out documents or control the a mouse. Peripheral devices are dependent on the computer system; external devices won't work without the help of a computer and only become functional when connected to a computer system.
There are many different peripheral devices, but they fall into three general categories