Glossary

Double buffering The process of using two frame buffers for smooth animation. Graphical contents of one frame buffer are displayed while updates occur on the other buffer. When the updates are complete, the buffers are switched. Only complete images are displayed, and the process of drawing is not shown. The result is the appearance of smooth animation.

DIMM Dual In-line Memory Module. These memory modules provide a 64- bit data path for improved system performance.

Eight-bit color The color range possible with an eight-bit graphics system. Each pixel in an 8-bit system can display one of 256 colors (28) at any given time. These colors are typically obtained from a color map.

expansion slot A slot inside the computer, connected to the system board, that can be used for accessory boards.

extended memory Memory which can be addressed by the processor in the area of memory above the first 1 MB.

Frame buffer Display memory that temporarily stores (buffers) a full frame of picture data at one time. Frame buffers are composed of arrays of bit values that correspond to the display's pixels. The number of bits per pixel in the frame buffer determines the complexity of images that can be displayed.

Graphical user interface (GUI) The graphical user interface (GUI) provides the user with a method of interacting with the computer and its special applications, usually via a mouse or another selection device. The GUI usually includes such things as windows, an intuitive method of manipulating directories and files, and icons.

IDE Integrated Device Electronics. An interface standard for communications between the computer and a hard disk or CD-ROM.

IRQ Interrupt Request. A signal, that when received by the processor, halts the current process and allows a different task to be undertaken.

ISA Industry Standard Architecture. The ISA bus is the system bus originally used on the IBM PC/XT and IBM PC/AT computers. The version of the bus used on the AT is often referred to as the AT bus. The XT bus is 8 bits wide and the AT bus is 16 bits wide. The AT bus has become a de facto industry standard.

jumper An electrically-conductive part that is used to connect two or more points on a circuit board.

Commonly used to select configuration options.

LAN Local Area Network. A general- purpose communications network that interconnects a variety of devices within a limited geographical area. A LAN might connect computers on adjacent desks, within a building, or

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