NOTE: This glossary includes terms presented in AMEDD Computer Literacy I and II.
Terms first introduced in AMEDD Computer Literacy II are marked by an asterisk; if
presented in both subcourses, there is a double-asterisk.
abacus: an ancient calculating device composed of a frame of rods representing
decimal columns and beads that are moved on the rods to form digits. (1-6a)
access time: the time the computer takes to locate and transfer instructions or data to
or from storage. (2-8e)
address: a number identifying a storage location from which data are to be retrieved or
analog computer: used primarily in engineering or scientific computing, it measures
continuous physical or electrical magnitudes, such as pressure, temperature, current
voltage, etc. (2-2b)
application program: a sequence of instructions written to solve a specific problem.
auxiliary storage: a supplement to the main storage; normally supplied by magnetic
disks, magnetic drums, magnetic tape, or magnetic cards. (2-8a)
batch processing: a technique in which a number of similar items or transactions are
accumulated and then processed periodically as a group or batch. (In contrast to on-
line processing.) (3-13a)
*binary code: a system for representing things by combinations of two symbols, such
as 1 or 0, TRUE or FALSE, presence or absence of voltage. (1-1)
*binary number system: a number system that uses two as its base and expresses
numbers as strings of is and Os. (1-5b)
bit: short for binary digit, the smallest unit of information recognizable to a computer. A
single bit can be either "on" (1) or "off" (0). All computer information is encoded as a
string of bits. A 16-bit microprocessor is one that can digest 16 binary digits at a time.
*bubble memory: a recently developed compact memory device represented by
magnetized spots or bubbles. The bubbles rest on thin wafers of garnet (a
semiconductor material) in a magnetic field. Data on bubble memory are not lost when
the power is shut off. (4-3)