MPE/iX Glossary of Terms and Acronyms (32650-90887)

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Glossary of Terms
references to baud rate.
beginning of tape (BOT) A mark on a magnetic tape indicating where the tape drive
will start reading or writing data.
beta test The designation given to a product test in a limited customer environment.
For example, Hewlett-Packard tests its products at selected external
customer sites before they are publicly released.
binary A method of representing numbers, alphabetic characters, and symbols in
digital computers. Binary is the base two numbering system that uses only
two digits, 0's and 1's, to express numeric quantities.
binary coded decimal (BCD) A decimal notation in which individual decimal digits are
each represented by a group of four bits.
binary synchronous communications (BSC) A data link protocol, also referred to as
BISYNC. A line control station in a data communications system.
bit A binary digit; the number 0 or 1 in the base 2 numbering system (0
represents OFF, and 1 represents ON). Usually eight bits equal one byte. A
bit is the smallest unit of information in a digital computer.
bit bucket Computer jargon referring to a nonexistent computer storage area. The bit
bucket is used when the system-defined $NULL file is specified in a
command line as an output file. The associated write request is accepted
by MPE/iX, but no physical output is actually performed.
bit-oriented protocol (bop) A communications protocol that does not recognize a
character as sequences of bits.
bit rate The speed at which bits are transmitted. The bit rate is usually kilobits
per second (Kb/s) or megabits per second (Mb/s).
bits per inch (bpi) A measurement of data density. It expresses the number of bits
recorded per inch of recording surface.
bits per second (bps) A measure of transmission speed over a communications channel.
block A group of one or more logical records treated as a single piece of data.
blocked A state of suspension for a process.
blocked record A physical record that contains more than one logical record. The
opposite of unblocked record.
block mode A terminal processing mode. It transmits groups, or blocks of characters
all at once, instead of one character at a time.
board A piece of fiberglass that holds integrated circuits (ICs or chips) and
contains the connections between chips. A board is also called a card or
circuit board.
Boolean A data type with a value that is either TRUE or FALSE (binary 1 or 0).
boot The process of loading and initializing an operating system. The term
booting is derived from the phrase "pulling yourself up by your
bootstraps."