User guide

support.dell.com Glossary 3
communications between the micro-
processor and RAM.
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Eight contiguous bits of information; the
basic data unit used by your computer.
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Abbreviation for Bundesamt fur Zulassun-
gen in deer Telecommunication.

Abbreviation for Celsius.
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To facilitate quicker data retrieval, a stor-
age area for keeping a copy of data or
instructions. For example, your comput-
er's BIOS may cache ROM code in faster
RAM. Or a disk-cache utility may reserve
RAM in which to store frequently access-
ed information from your computer's disk
drives; when a program makes a request
to a disk drive for data that is in the cache,
the disk-cache utility can retrieve the data
from RAM faster than from the disk drive.
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On the bottom of an expansion card, the
metal-contact section that plugs into an
expansion-card connector.
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Abbreviation for cold cathode fluorescent
tube.
%' (
Abbreviation for compact disc read-only
memory. CD-ROM drives use optical
technology to read data from compact
discs. CDs are read-only storage devices;
you cannot write new data to a CD with
standard CD-ROM drives.
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Abbreviation for color graphics adapter.

Abbreviation for comprehensive input/
output.

Abbreviation for centimeter(s).
( 
Acronym for complementary metal-oxide
semiconductor. In computers, CMOS
memory chips are often used for NVRAM
storage.
 (
The MS-DOS device names for the first
through fourth serial ports on your com-
puter are COM1, COM2, COM3, and
COM4. MS-DOS supports up to four serial
ports. However, the default interrupt for
COM1 and COM3 is IRQ4, and the default
interrupt for COM2 and COM4 is IRQ3.
Therefore, you must be careful when you
configure software that runs a serial de-
vice so that you do not create an interrupt
conflict.
 
The MS-DOS device name for the con-
sole, which includes your computer's
keyboard and text displayed on the
screen.
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When you boot your computer, MS-DOS
runs any commands contained in the text
file
config.sys
(before running any com-
mands in the
autoexec.bat
file). A
config.sys
file is not required to boot
MS-DOS, but provides a convenient place
to run commands that are essential for
setting up a consistent computing envi-
ronment—such as loading device drivers
with a device= statement.

A chip or expansion card that controls the
transfer of data between the micro-
processor and a peripheral such as a
diskette drive or the keyboard.
*
The first 640 KB of RAM. Unless they are
specially designed, MS-DOS programs
are limited to running in conventional
memory. See also EMM, expanded mem-
ory, extended memory, HMA, memory
manager, upper memory area, and XMM.

A coprocessor relieves the computer's
microprocessor of specific processing
tasks. A math coprocessor, for example,