Xerox 721 Message Manual page 327

GLOSSARY
GLOSSARY-34
MIS management information systems
MPU microprocessor unit
MTU magnetic tape unit (refers to the 9-track magnetic tape drive; also
referred to as "magnetic tape drive")
OCR optical character recognition
OCS operator communications subsystem
OLI online interface
OS operating system
OSDS operating system diagnostic software
OSEXEC operating system executive
OSS operating system software
PC personal computer
PCC printer carriage control
PC UI personal computer user interface
PDL print description language
PE phase encoded
ppm pages per minute
PQA print quality adjustment
PROM programmable read-only memory
PSC printer subsystem controller
pt point
PWBA printed wiring board assembly
QIC 1/4 inch cartridge
XEROX 4635 LASER PRINTING SYSTEM MESSAGE GUIDE