Toshiba Portege 3500, User Manual

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Glossary
4 Portégé 3500
binary: The base two number system composed of zeros and ones (off or
on), used by most digital computers. The right most digit of a
binary number has a value of 1, the next a value of 2, then 4, 8, 16,
and so on. For example, the binary number 101 has a value of 5.
See also ASCII.
BIOS: Basic Input Output System. The firmware that controls data flow
within the computer. See also firmware.
bit: Derived from "binary digit," the basic unit of information used by the
computer. It is either zero or one. Eight bits is one byte. See also
byte.
board: A circuit board. An internal card containing electronic
components, called chips, which perform a specific function or
increase the capabilities of the system.
boot: Short for bootstrap. A program that starts or restarts the computer.
The program reads instructions from a storage device into the
computer’s memory.
bps: Bits per second. Typically used to describe the data transmission
speed of a modem.
buffer: The portion of the computer’s memory where data is temporarily
stored. Buffers often compensate for differences in the rate of flow
from one device to another.
bus: An interface for transmission of signals, data or electric power.
byte: The representation of a single character. A sequence of eight bits
treated as a single unit; also the smallest addressable unit within
the system.
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cache memory: High speed memory which stores data that increases
processor speed and data transfer rate. When the CPU reads data
from main memory, it stores a copy of this data in cache memory.
The next time the CPU needs that same data, it looks for it in the
cache memory rather than the main memory, which saves time.
The computer has two cache levels. Level one is incorporated into
the processor and level two resides in external memory.
capacity: The amount of data that can be stored on a magnetic storage
device such as a diskette (floppy disk) or hard disk. It is usually
described in terms of kilobytes (KB), where one KB = 1024 bytes
and megabytes (MB), where one MB = 1024 KB.
card: Synonym for board . See board.
CardBus: An industry standard bus for 32-bit PC Cards.
CD-ROM: A Compact Disk-Read Only Memory is a high capacity disk
that can be read from but not written to. The CD-ROM drive uses a
laser, rather than magnetic heads, to read data from the disk.
character: Any letter, number, punctuation mark, or symbol used by the
computer. Also synonymous with byte.
chassis: The frame containing the computer.