Glossary

239

Terms

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.

 

central processing unit (CPU) — The chip that functions as the “brain”

 

of the computer. It takes information from outside sources, such as

 

memory or keyboard input, processes the information, and sends the

 

results to another device that uses the information.

 

character — Any letter, number, or symbol you can use on the

 

computer. Some characters are non-printing characters, such as a

 

paragraph break in a word-processing program. A character occupies

 

one byte of computer storage.

 

chip — A small piece of silicon containing computer logic and circuits

 

for processing, memory, input/output, and/or control functions. Chips

 

are mounted on printed circuit boards.

 

click — To press and release the AccuPoint control button or mouse

 

button without moving the AccuPoint or mouse. In Windows, this

 

refers to the left mouse button or primary AccuPoint control button,

 

unless otherwise stated. See also double-click.

 

color palette — A set of specified colors that establishes the colors that

 

can be displayed on the screen at a particular time.

 

compatibility — The extent to which computers, programs, or devices

 

can work together harmoniously, using the same commands, formats,

 

or language as another.

 

configuration — (1) The collection of components that make up a single

 

computer system. (2) How parts of the system are set up (that is,

 

configured).

 

controller — A device that controls the transfer of data from a computer

 

to a peripheral device and vice versa. For example, disk drives,

 

monitors, keyboards, and printers all require controllers.