IBM XT 5160 Technical Reference page 392

matrix printer. A printer in which each character is represented
by a pattern of dots; for example, a stylus printer, a wire printer.
Synonymous with dot printer.
MD. 1,048,576 bytes.
mega (M). Prefix 1,000,000.
megahertz (MHz). 1,000,000 hertz.
memory. Term for main storage.
meter (m). A unit of length (equivalent to 39.37 inches).
MFM. Modified frequency modulation.
MHz. Megahertz; 1,000,000 hertz.
micro (J-t). Prefix 0.000,001.
microcode. (1) One or more microinstructions. (2) A code,
representing the instructions of an instruction set, implemented in
a part of storage that is not program-addressable.
microinstruction. (1) An instruction of microcode. (2) A basic
or elementary machine instruction.
microprocessor. An integrated circuit that accepts coded
instructions for execution; the instructions may be entered,
integrated, or stored internally.
microsecond (J-ts). 0.000,001 second.
milli (m). Prefix 0.001.
milliampere
(rnA).
0.001 ampere.
millisecond (ms). 0.001 second.
mnemonic. A symbol chosen to assist the human memory; for
example, an abbreviation such as "mpy" for "multiply."
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