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Appendix C
communicate properly, a printer must be configured
to operate at the same baud rate as its host
computer.
bit Contraction of binary digit. A bit is a digit in the binary
number system, represented by a 0 or a 1. A bit is
the smallest unit of storage in a digital computer,
where 0 and 1 are represented by different voltages.
Groups of bits form other units of storage called
nibbles, bytes, and words.
bold A print attribute specifying text of a heavy line
thickness. See also character weight.
Boot-up The start-up procedure which causes a computer
operating system to be loaded into main memory.
buffer A reserved area in memory that data is written to and
read from during data transfers.
bus A circuit for the transfer of data or electrical signals
between two devices.
byte A group of consecutive bits forming a unit of storage
in a digital computer and used to represent one
alphanumeric character. A byte usually consists of 8
bits, but may contain more or fewer bits, depending
on the computer or protocol.
C
character cell The invisible rectangular space occupied by a
character, including the white space around the
character. The height of a cell remains constant even
with changes in the current line spacing, and the
width is equal to the current character spacing. Used
as a unit of spacing.
character proportion The ratio of character height to character width. See
also compressed and expanded.
character set A set of codes, each of whic h represents a control or
printable character, including symbols, punctuation,
numbers, diacritical markings, and alphabet
characters. Each character is assigned a unique
address in memory.
character weight The degree of lightness and thickness of printed text.
For example: “Bold” refers to a heavy or thick
character weight, as shown in this sentence.
“Medium,” “normal,” or “book weight” refer to the
character weight used in this sentence.
checksum A value used to verify microcode correctness.
coax Coaxial cable. An electrical signal conductor
consisting of a single wire surrounded by insulation