B

bandwidth

Usually used in reference to the amount of data per unit of time that must move from one point to another, such as from CD-ROM to processor.

BIOS

Basic input/output system. A set of routines that works closely with the hardware to support the transfer of information between elements of the system, such as memory, disks, and the monitor. Although critical to performance, the BIOS is usually invisible to the end user; however, programmers can access it.

BIOS enumerator

Responsible in a non-ACPI Plug and Play system for identifying all hardware devices on the motherboard of the computer. The BIOS supports an API that allows all Plug and Play computers to be queried in a common manner.

bit map

Representation of characters or graphics by individual pixels arranged in rows (horizontal) and columns (vertical). Each pixel can be represented by either 1 bit (simple black and white) or up to 32 bits (high-definition color).

bit-mapped graphics

Images created with matrices of pixels or dots. Also raster graphics.

bit specifications

Number of colors or levels of gray that can be displayed at one time. Controlled by the amount of memory in the computer's graphics controller card. An 8-bit controller can display 256 colors or levels of gray; a 16-bit controller, 64,000 colors; and a 24-bit controller, 16.8 million colors.

bpp

Bits per pixel. The number of bits used to represent the color value of each pixel in a digitized image.

bps

Bits per second. The number of bits transferred per second in a data communications system. A measure of speed.

brightness

The value associated with a pixel, representing its gray value from black to white.

broadcast architecture

The set of technologies that enable PCs to receive broadcast data.

buffer

A reserved portion of memory in which data is temporarily held pending an opportunity to complete its transfer to or from a storage device or another location in memory.

bus enumerator

In a Plug and Play system, a bus device driver that detects devices located on a specific bus and loads information about devices into the hardware tree.