Glossary-10
GLOSSARY
monitor: A device that uses rows and
columns of pixels to display alphanu-
meric characters or graphic images. See
CRT.
motherboard: A name sometimes used
to refer to the main printed circuit board
in processing equipment. It usually
contains integrated circuits that perform
the processor’s basic functions and
provides connectors for adding other
boards that perform special functions.
Sometimes called a main board.
MPEG: Moving picture coding expert
group is an industry standard architec-
ture for compression of video signals.
N
non-system disk: A formatted diskette
(floppy disk) you can use to store
programs and data but you cannot use
to start the computer. See system disk.
nonvolatile memory: Memory, usually
read-only (ROM), that is capable of
permanently storing information.
Turning the computer’s power off does
not alter data stored in nonvolatile
memory.
numeric keypad overlay: A feature that
allows you to use certain keys on the
keyboard to perform numeric entry, or
to control cursor and page movement.
O
OCR: Optical Character Recognition
(reader). A technique or device that
uses laser or visible light to identify
characters and input them into a storage
device.
OCR wand: A device that reads, using
an optical device, hand written or
machine printed symbols into a
computer. See also OCR.
on-line state: A functional state of a
peripheral device when it is ready to
receive or transmit data.
operating system: A group of programs
that controls the basic operation of a
computer. Operating system functions
include interpreting programs, creating
data files, and controlling the transmis-
sion and receipt (input/output) of data
to and from memory and peripheral
devices.
output: The results of a computer
operation. Output commonly indicates
data 1) printed on paper, 2) displayed at
a terminal, 3) sent through the serial port
of internal modem, or 4) stored on some
magnetic media.
P
parallel: Refers to two or more pro-
cesses or events that can occur
simultaneously, and without interfering
with each other. See also serial.
parallel interface: Refers to a type of
information exchange that transmits
information one byte (8 bits) at a time.
See also serial interface.

monitor