Controller

A processor, interface, port, or adapter that translates data between the CPU and a peripheral device, such as a hard disk, diskette drive, keyboard, or video monitor. Controllers convert data from one format to another, match speeds between devices that operate at different speeds, and isolate peripheral hardware from software.

CPU

Central Processing Unit. The primary device that interprets instructions, performs tasks, keeps track of stored data, and controls input and output operations. See also Processor.

Device

A piece of computer equipment that performs a specific task, such as a disk drive, a monitor, a printer, or a scanner. Also called a peripheral.

Device driver

A file containing instructions that allow your computer to recognize and communicate with a device. The device may be a printer, monitor, or other type of device.

Dual Inline Package. A type of chip which has two rows of downward-pointing pins.

DMA

Direct Memory Access channel. A channel for transferring data from your computer to or from peripherals without involving the CPU resources.

2 Glossary