NEC POWERMATE 8100 RELEASE NOTES, Руководство пользователя

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8 Glossary
checksum
A number, calculated from a block of data, used to verify the
integrity of that data. For example, a modem could send a block of
data and include the number of 1’s that occur in the block. The
receiving modem could count the number of 1’s it receives and
compare its own number with the transmitted number. If the numbers
are the same, the transmission was probably OK.
clock
Electronic timer (oscillator) used to synchronize computer operations.
The oscillator generates the timing pulses that coordinate and enable
the flow of data within a digital device. Also a circuit powered by
battery that keeps track of the date and time for human and various
system requirements.
clock speed
The frequency at which a clock oscillates. In microcomputers,
measured in MHz. The faster the clock, the faster the computer can
compute.
CMOS
Complementary Metal Oxide Semiconductor. A chip on the system
board that contains nonvolatile memory. CMOS is backed up by an
internal lithium battery that preserves clock/calendar data and system
configuration parameters stored in CMOS.
codec
Coder-decoder. Used primarily with Internet phone and video
conferencing products, this software compresses digitized data and
decompresses it at the other end, allowing for faster data transfer and
less delays
cold boot
Process of starting up the computer by turning on the power. If power
is already on, the process means to turn off the computer and turn it
on again. A cold boot reinitializes all devices.
compression
Any scheme for recording data with fewer bits. For example, stating
how many times something occurs can be shorter than stating each
occurrence. It is shorter to say “print a million white pixels” than to
say “print white pixel number one, print white pixel number two . . .”