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Glossary
5.375 x 8.375 ver 2.3
BIOS (basic input/output system) — Basic instructions, stored in read-
only memory (ROM), containing the information the computer
needs in order to check hardware and load the operating system
when you start up the computer.
bit: — Short for “binary digit.” A bit is the smallest unit of information
used by a computer. A group of eight bits is a byte. See also byte.
bits per second (bps) — A way of measuring the speed at which
information is passed between two devices. The basic measure used
in modem communications, bps is similar, but not identical, to the
baud rate. See also baud rate.
boot — To start the computer. The term “boot” originates from bootstrap
program (as in “pulling itself up by its bootstraps”), a program that
loads and initializes the operating system. See also reboot.
boot disk — See system disk.
boot priority (startup sequence) — The order in which the computer
accesses its disk drives to locate the startup files. Under the default
startup sequence, the computer looks for the startup files in the
diskette drive before checking the hard disk.
bus — An electrical circuit that connects the central processing unit
(CPU) with other parts of the computer, such as the video adapter,
disk drives, and ports. It is the pathway through which data flows
from one device to another. See also bus speed, frontside bus.
bus speed — The speed at which the central processing unit (CPU)
communicates with the other parts of the computer.
byte — A sequence of eight bits. A byte is the smallest addressable unit
of data. See also bit, gigabyte, kilobyte, megabyte.
C
cache — A section of very fast memory in which frequently used
information is duplicated for quick access. Accessing data from
cache is faster than accessing it from the computer’s main memory.
See also CPU cache, L1 cache, L2 cache.
CD — An individual compact disc. See also CD-ROM.
CD-ROM (compact disc read-only memory) — A form of high-
capacity storage that uses laser optics instead of magnetic means for
reading data. See also CD. Compare DVD-ROM.
