Toshiba Satellite C640 - Manual (Page 160)

User’s Manual Glossary-10
Glossary
M
main board: See motherboard.
megabyte (MB): A unit of data storage equal to 1024 kilobytes. See also
kilobyte.
megahertz: A unit of wave frequency that equals 1 million cycles per
second. See also hertz.
menu: A software interface that displays a list of options on the screen.
Also called a screen.
microprocessor: A hardware component contained in a single integrated
circuit that carries out instructions. Also called the central
processing unit (CPU), one of the main parts of the computer.
mode: A method of operation, for example, the Boot Mode, Sleep Mode or
the Hibernation Mode.
modem: Derived from modulator/demodulator, a device that converts
(modulates) digital data for transmission over telephone lines and
then converts modulated data (demodulates) to digital format where
received.
monitor: A device that uses rows and columns of pixels to display
alphanumeric characters or graphic images. See also 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.
N
non-system disk: A formatted floppy diskette 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.
online state: A functional state of a peripheral device when it is ready to
receive or transmit data.