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mA        Milliampere

Mac       Macintosh (Apple Macintosh Computer)

MAC       Media/Medium Access Control

MAC     * Multiple Access Computers

.MAC      MacPaint (file name extension) +

          Macro (file name extension)

MACH      Multilayer Actuator Head [Epson]

MADE      Manufacturing and Automated Design Engineering

MADYMO    Mathematical Dynamic Modeling [TNO]

MAE       Metropolitan Area Ethernet

MADYMO    Minimal Architecture for Generalized Markup Applications

mAh       Milliampere-Hour

MAI       Multiple Applications Interface

.MAI      Mail (file name extension)

MAN       Manual [Unix] + Metropolitan Area Network

MANIAC  * Mathematical Analyzer Numerical

          Integrator and Computer

MANPAGE   Manual Page [Unix]

MAP       Maintenance Analysis Procedures +

          Manufacturing Automation Protocol +

          Memory Allocation Map

.MAP      Linker Map (file name extension)

MAPI      Mail/Messaging Applications Programming

          Interface [Microsoft]

MAPICS    Manufacturing, Accounting and Production

          Information Control System [IBM]

MARC      Machine Readable Cataloging +

          Multi-Technology Automated Reader Card

MARVEL    Machine-Assisted Realization of the Virtual

          Electronic Library [Library of Congress]

MASM      Macro Assembler [Microsoft]

MASS      Maximum Availability and Support

          Subsystem [Parallan]

MAT       Maintenance Access Terminal

MAU       Media Access/Adapter Unit + Multistation Access Unit

MAVDM     Multiple Application VDM

MAX       Maximum

MB        Megabyte (1,024 kilobytes) +

          Middle Button (of 3 button Mouse)

MBASIC    Microsoft BASIC [Microsoft]

MBCS      Multi-Byte Character Set [IBM]

MBONE     Multicast Backbone [Internet]

MBps      Megabytes Per Second

Mbps      Megabits Per Second

MBR       Master Boot Record

MBX       Mailbox

MCA       Micro Channel Adapter/Architecture [IBM]

MCAD      Mechanical Computer Aided Design

MCB       Memory Control Block

MCF       Meta Content Framework

MCGA      Multicolor Graphics Array

MCI       MCI Communications Corp. (name from initials of

          original company - Microwave Communications, Inc.) +

          Media Control Interface [Microsoft]

MCL       Microsoft Compatibility Labs [Microsoft]

MCM       Multi-Chip Module

MCNE      Master Certified Novell Engineer [Novell]

MC-PGA    Metallized Ceramic - Pin Grid Array

MCPS      Microsoft Certified Product Specialist [Microsoft]

MC-QFP    Metallized Ceramic - Quad Flat Pack

MCR       Modem Control Register

MCSE      Microsoft Certified Systems Engineer [Microsoft]

MCU       Microcontroller Unit + Multi-Chip Unit [DEC] +

          Multipoint Control Unit

MD        Make Directory + Mini Disk [Sony] + Monochrome Display

MDA       Monochrome Display Adapter +

          Multidimensional Analysis

MDDBMS    Multidimensional Data Base Management System

.MDF      Menu Definition File (file name extension)

MDI       Memory Display Interface +

          Multiple Document Interface

MDIC      Manchester Decoder and Interface Chip [AT&T]

MDK       Multimedia Developers Kit [Microsoft]

MDLP      Modile Data Link Protocol

MDR       Minimum Design Requirement

MDY       Month Day Year

.ME       Opening Information (file name extension) (As in READ.ME)

MEB       Memory Expansion Board

MEG       Megabyte

MEM       Memory

.MEN      Menu (file name extension)

MERCI     Multimedia European Research Conferencing Integration

MES       Manufacturing Execution System

MESI      Modified, Exclusive, Shared and Invalid (protocol)

MET       Memory Enhancement Technology [Hewlitt-Packard]

.MET      Metafile (file name extension)

MFC       Microsoft Foundation Class [Microsoft]

MFFS      Microsoft Flash File System [Microsoft]

MFLOPS    Million Floating Point Operations Per Second

MFM       Modified Frequency Modulation

MFP       Multi-Function Peripheral/Product

MFPI      Multifunction Peripheral Interface

MFS       Macintosh File System [Macintosh] +

          Magnetic Tape Field Search + Memory File System

          Modified Filing System [Revelation Technologies]

MFT       Master File Table +

          Multiprogramming with a Fixed number of Tasks

MGA       Monochrome Graphics Adapter

MGE       Modular GIS Environment

MGET      Multiple Get [Unix]

MGML      Minimal Generalized Markup Language

MGR       Manager

MHS       Message Handling Service + Message Handling System

MHz       Megahertz

MI        Management Interface

MIB       Management Information Base

MICR      Magnetic Ink Character Recognition

MICRO     One-millionth

MICS      Macro Interpretive Commands

MIDI      Musical Instrument Digital Interface

MIF       Management Information Format

.MIF      Management Information Files (file name extension)

MIG       Metal In Gap

MII       Microsoft/IBM/Intel

MIL       Machine Interface Layer [Go Corporation] +

.MIL      Military (Domain name) [Internet]

MIM       Metal-Insulator-Metal (screen)

MIMD      Multiple Instruction Multiple Data Stream (processor)

MIME      Multipurpose Internet Mail Extension [Internet]

MI/MIC    Mode Indicate/Mode Indicate Common

MIN       Minimum + Mobile Identification Number

MINUET    Minnesota Internet Users Essential Tools [Internet]

MIPS      Million Instructions Per Second

MIS       Management Information System +

          Multimedia Information Sources [Internet]

MISC      Miscellaneous

MIX       Member Information Exchange

MKDIR     Make Directory

ML        Machine Language + Meta Language

MLAPI     Multilingual Application Programming Interface

MLC       Multilayer Ceramic +

          Multilevel Cell (program) [Internet]

MLE       Multi-Line Editor

MLID      Multi-Link Interface Driver

MLM       Mailing List Manager [Internet]

MLPPP     Multilink PPP

MM        Minutes + Month

MMA       Microcomputer Managers Association

MMC       Matched Memory Cycle + Microcomputer Marketing Council +

          Microsoft Management Console [Microsoft]

MMCD      MultiMedia Compact Disk

MMCX      Multimedia Communication Exchange [Lucent Technologies]

MMI       Man-Machine Interface

MMIS      Materials Manager Information System

MMPM      Multi Media Presentation Manager

MMU       Memory Management Unit

MMVF      Multimedia Video File [NEC]

MMX       Matrix Manipulation Extensions [Intel] +

          Multimedia Extensions

MNOS      Metal Nitride Oxide Semiconductor

MNP       Microcom Networking Protocol [Microcom]

.MNU      Menu (fine name extension)

MO        Magneto-Optical (disk drive)

MOB       Memory-Order Buffer

MOBO      Mother Board

MOD       Module + Modulus

MODEM     Modulator Demodulator

MOHLL     Machine Oriented High Level Language

MOLAP     Multidimensional On-Line Analytical Processing

MOM       Manufacturing Operations Management +

          Message-Oriented Middleware +

          Microsoft Office Manager [Microsoft]

MONET     Multiwavelength Optical Networking

MONO      Monaural

MOO       MUD, Object Oriented [Internet]

MOP       Maintenance Operations Protocol

MOPS      Million Operations Per Second

MOS       Magneto-Optic Storage + Mean Opinion Score +

          Metal Oxide Semiconductor

MOSFET    Metal Oxide Semiconductor Field Effect Transistor

MOTD      Message Of The Day

MOV       Metal Oxide Varistor + Move

MOVS      Move String

MP        Massively Parallel (processing) + Multiple Processors

MPC       Multimedia Personal Computer + Multipath Channel

MPCS      Mission Planning and Control Station (Software)

MPE       Multiple Programming Executive [HP]

MPEG      Motion Picture Experts Group

MPI       Message Passing Interface + Multiprecision Integer

MPM       Message Passing Library [IBM]

MPMD      Multiple Processor/Multiple Data

MPOA      Multi-Protocol over Asynchronous-Transfer-Mode

MPP       Massively Parallel Processing +

          Message Posting Protocol + Message Processing Program

MPQP      Multi-Protocol Quad Port [IBM]

MPR       Multipart Repeater + Multi Protocol Router [Novell]

MPS       Multiprocessor Specification

MPTN      Multi-Protocol Transport Network

MPTS      Multi-Protocol Transport Services

MPU       Microprocessor Unit

MQI       Message Queue Interface

MR        Magneto Resistive + Modem Ready

MRCF      Microsoft Realtime Compression Format

MRCI      Microsoft Realtime Compression Interface

MRI       Magnetic Resonance Imaging

MRM       Most Recently-Used Master

MRO       Multi-Region Operation

MRP       Materials Requirement Planning

MRPL      Main Ring Path Length

MRS       Media Recognition System

MRT       Mean Repair Time

MRU       Maximum Receive Unit

MS        Memory System + Message Store + Microsecond +

          Microsoft Corporation + Millisecond

MSACM     Microsoft Audio Compression Manager [Microsoft]

MSAU      Multi-Station Access Unit

MSAV      Microsoft Anti Virus [Microsoft]

MSB       Most Significant Bit

MSBF      Mean Swaps Between Failures

MSCDEX    Microsoft Compact Disc Extensions [Microsoft]

MSD       Mass Storage Device + Most Significant Digit +

          Microsoft System Diagnostics [Microsoft]

MSDN      Microsoft Developer Network [Microsoft]

MS-DOS    Microsoft - Disk Operating System [Microsoft]

MSDR      Multiplexed Streaming Data Request

MSDS      Microsoft Developer Support [Microsoft]

MSFR      Minimum Security Function Requirements [IBM]

MSG       Message

.MSG      Program Message (file name extension)

MSI       Medium Scale Integration

MSIE      Microsoft Internet Explorer [Microsoft]

MSL       Map Specification Library + Mirrored Server Link

MSMQ      Microsoft Message Queue-Server [Microsoft]

MSN       Microsoft Network [Microsoft]

MSO       Multiple-Systems Operator

.MSP      Microsoft Paint (file name extension) [Microsoft]

MSRP      Manufacturer Suggested Retail Price

MSS       Mass Storage System +

          Multiprotocol Switched Services [IBM]

MSTS      Microsoft Terminal Server [Microsoft]

MSW       Machine Status Word

MTA       Message Transfer Agent + Multiple Terminal Access

MTBB      Mean Time Between Breakdowns

MTBF      Mean Time Between Failures

MTBJ      Mean Time Between Jams

MTF       Microsoft Tape Format [Microsoft] +

          Modulation Transfer Function

MTRP      Maximum Transfer Rate Performance

MTS       Message Transfer Service/System +

          Microsoft Transaction Server [Microsoft] +

          Multichannel Television Sound

MTT       Multi-Transaction Timer

MTTD      Mean Time To Diagnose

MTTF      Mean Time To Failure

MTTR      Mean Time To Repair

MTU       Maximum Transmission Unit

MUA       Mail User Agent

MUD       Multi-User Dialogue/Dimension/Domain/Dungeon [Internet]

MUL       Multiply

MULTICS   Multiplexed Information and Computing Service

MUMPS     Massachusetts General Hospital Utility

          Multi-Programming System (Programming Language)

MUSE      Multi-User Shared Environment

MUT       Monitor Under Test

MUX       Multiplexer

MV        Millivolt

MVB       Multimedia Viewer Book

MVC       Multimedia Viewer Compiler

MVDM      Multiple Virtual DOS Machines

MVGA      Monochrome Video Graphics Array

MVIP      Multi-Vendor Integration Protocol

MVP       Multimedia Video Processor

MVS       Multiple Virtual Storage

MVT       Multiprogramming with a Variable number of Tasks

MX        Mail Exchanger [Internet]

MXS       Microsoft Exchange Server [Microsoft]

MZR       Multiple Zone Recording


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NAC       Network Adapter Card

NACD      National Association of Computer Dealers

NACS      National Advisory Committee on Semiconductors

NAE       Not Above or Equal

NAK       Negative Acknowledgment

NAM       Number Assignment Module

NAMPS     Narrow-Band Analog Mobile Phone Service [Motorola]

NAND      Not And

NANO      One thousand-millionth

NAP       Network Access Point

NAPLPS    North American Presentation Level Protocol

          Syntax (graphics)

NAS       Network Access Server + Network Application Support [DEC]

NASA      National Aeronautics and Space Administration

NASDAQ    National Association of Securities Dealers

          Automatic Quotation

NASI      NetWare Asynchronous Services Interface [Novell]

NASIRC    NASA Automated Systems Internet Response Capability

NASKER    NASA Ames Kernel (benchmark)

NAT       Network Address Translators

NAU       Network Addressable Unit

NAWS      Negotiate About Window Size

NBE       Not Below or Equal

NBI       Nothing But Initials

NBS       Narrowband Socket + National Bureau of Standards +

          Numeric Backspace

NC        Network Computer + No Carry + Numerical Control

NCA       Network Communications Adapter +

          Network Computing Architecture [Oracle]

NCC       Network Control Center

NCD       Network Computing Device

.NCF      Netware Command File [Novell]

NCGA      National Computer Graphics Association

NCIC      National Crime Information Center

NCMT    * Numerical Control for Machine Tools

NCOS      Network Computer Operating System

NCP       NetWare Core Protocol + Not Copy Protected +

          Network Control Processor/Program/Protocol

NCR       National Cash Register (Company)

NCSA      National Center for Supercomputing Applications

NCSC      National Computer Security Center

NCSI      Network Communications Services

          Interface [Network Products Corp.]

NDB       Non-Directional Beacon

NDDK      Network Device Development Kid [Microsoft]

NDEF      Not to be Defined

NDIS      Network Device/Driver Interface Specification

NDL       Network Data Language

NDN       Non-Delivery Notice

NDP       Numeric Data Processor

NDR       Network Data Representation

NDRO      Non-Destructive Read Out

NDS       NetWare Directory Service [Novell]

.NDX      Index (file name extension)

NEC       Nippon Electric Company

NED       NASA Extragalactic Database [NASA]

NEG       Negative + Negate

NEMA      National Electrical Manufacturers Association

NEP       Network Entry Point

NES       National Education Supercomputer

NEST      Novell Embedded Systems Technology [Novell]

.NET      Networks (Domain Name) [Internet]

NetBIOS   Network Basic Input/Output System [IBM]

NetBEUI   NetBIOS Extended User Interface [IBM]

NETMON    Network Monitor

.NEW      New Information (file name extension)

NEWS      NetWare Early Warning System [Frye Computer] +

          Network Extensible Window System

NEWS.     Current events [USENET Newsgroup Category]

NEXT      Near-End Crosstalk

NFF       No Fault Found

NFS       Network File System [Sun]

NG        No Good

NGE       Not Greater or Equal

NGI       Next-Generation Internet

NHC       National Hurricane Center

NHR       National Handwriting Recognition

NHRP      Next Hop Resolution Protocol

N/I       Non-Interlaced

NIA       Next Instruction Address

NIC       Network Information Center [Internet] +

          Network Interface Card +

          Numeric Intensive Computing

NICAD     Nickel-Cadmium

NICOLAS   Network Information Center OnLine Aid System [NASA]

NID       New Interactive Display [NEC] + Next ID

NII       National Information Infrastructure

NIM       Network Installation Management [IBM]

NIMH      Nickel-Metal Hydride

NIO       Native Input/Output

NIPS      Network I/Os Per Second

NIR       Network Information Retrieval

NIS       Network Information Service [Unix]

N-ISDN    Narrowband ISDN + National ISDN

NISO      National Information Standards Organization

NISP      Networked Information Services Project

NIST      National Institute for Standards and Technology

NITC      National Information Technology Center

NIU       Network Interface Unit

NJE       Network Job Entry (protocol) [IBM]

NL        New Line

NLE       Not Less or Equal

NLM       NetWare Loadable Module [Netware]

NLP       Natural-Language Processing

NLQ       Near Letter Quality

NLSFUNC   National Language Support Function

NLV       National Language Version [IBM]

NMI       Non-Maskable Interrupt

NMM       NetWare Management Map [NetWare]

NMOS      Negative Channel Metal-Oxide Semiconductor

NMP       Network Management Protocol [AT&T]

NMS       Network Management System [Novell]

NN        Network Node + No News [Internet]

NNI       Network to Network Interface

NNTP      Network News Transfer Protocol [Internet]

NOC       Network Operations Center

.NOM      Individual with Personal Site (Domain Name) [Internet]

NOP       No Operation

NOPAC     Network OPAC

NOR       Not Or

NOS       Network Operating System

NPA       Network Printer Alliance + Numbering Plan Area

NPI       Network Printer Interface

NPL       Nonprocedural Language

NPS       Novell Productivity Specialist [Novell]

NPTN      National Public Telecomputing Network

NPU       Natural Processing Unit

NPX       Numeric Processor Extension

NQS       Network Queing System [Cray]

NRC       National Research Council (Canada)

NREN      National Research and Education Network

NRZ       Not Return to Zero

NRZI      Non Return to Zero Inverted

NS        Nanosecond (one-bilionth of a second) +

          National Semiconductor (as in Ns16550 UART) +

          Network Supervisor + Non Stop

NSAP      Network Service Access Point

NSAPI     Netscape Server API [Netscape]

NSA POLY  National Security Agency Polygraph

NSERC     National Sciences and Engineering Research Council


NSF       National Science Foundation

NSFNET    National Science Foundation Network

NSI       NASA Science Internet

NSLOOKUP  Name Server Lookup [Unix]

NSM       Netscape Server Manager [Netscape]

NSP       Native Signal Processing [Intel] + Network Service


NSSC      NASA Standard Spacecraft Computer

NSTC      National Science and Technology Council

NSTL      National Software Testing Labs

NT        New Technology [Microsoft]

NT-1      Network Terminator Type 1

NTAS      NT Advamced Server [Microsoft]

NTF       No Trouble Found

NTFS      New Technology File System [Microsoft]

NTIA      National Telecommunications and

          Information Administration

NTIS      National Technical Information Service

NTRAS     NT Remote Access Services [Microsoft]

NTSA      NetWare Telephony Services Architecture [Novell]

NTSC      National Television Standards Committee

NTU       Network Termination Unit

NUI       Network User Identification +

          Network User Interface +

          Notebook User Interface [Go Corporation]

NUL       Null + (dummy device) + (no device)

NUMA      Non-Uniform Memory Access

NV        No Overflow

NVM       Non-Volatile Memory

NVOD      Near-Video On Demand

NVP       Nominal Velocity of Propagation

NVRAM     Non-Volatile Random Access Memory

NVT       Network Virtual Terminal +

          Novell Virtual Terminal [Novell]

NWS       NetWare Web Server [Netware]

NYM       Anonymous


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OAB       One-to-All Broadcast

OAD       Open Architecture Driver [Bernoulli]

OAG       Official Airline Guide + Online Air Guide

OAI       Open Applications Interface

OAS       One-to-All Scatter

OBD       On Board Diagnostics

OBEX      Object Exchange [Borland]

OBJ       Object

OC        Optical Carrier

OCE       Open Collaborative Environment [Apple]

OCF       Objects Components Framework [Borland]

OCL       Operation Control Language + Operator Control Language

OCR       Optical Character Recognition

OCS       On-Card Sequencer

OCX       OLE Custom Control

ODA       Open Document Architecture

ODAPI     Open Database Application Programming

          Interface [Borland]

ODBC      Object-Oriented Database Connectivity +

          Open Data Base Connectivity [Microsoft]

ODBMS     Object-Oriented Database Management System  (also

          see OODMS)

ODI       Open Datalink Interface [Novell] +

          Open Device Interconnect [NetWare]

ODIF      Open Document Interchange Format

ODL       Object Definition Language

ODM       Object Data Manager [IBM] +

          Optimized Distribution Model [Compaq]

ODMA      Open Document Management API

ODP       Open Distributed Processing

ODS       Open Data Services [Microsoft] +

          Operational Data Store

ODSI      Open Directory Service Interface [Microsoft]

ODT       Open Desktop

OEM       Original Equipment Manufacturer

OEP       Operand Execution Pipeline

OF        Overflow Flag

OFB       Output Feedback (mode)

OFDM      Orthogonal Frequency Division Multiplexing

OFMT      Output Format for Numbers

OFS       Object File System [Microsoft] + Output Field Separator

OFX       Open Financial Exchange

OH        Off Hook

OIDL      Object Interface Definition Language

OIS       Office Information System

OLAP      On-Line Analytical Processing

OLCP      On-Line Complex Processing

.OLD      Old version (file name extension)

OLE       Object Linking and Embedding [Microsoft]

OLGA      On-Line Guitar Archive

OLI       Optical Line Interface [AT&T]

OLMC      Output Logic Macrocell

OLSP      On-Line Service Provider

OLTP      On-Line Transaction Processing

OM        Object Manager

OMA       Object Management Architecture [Microsoft]

OME       Open Messaging Environment (protocol)

OMF       Object Module Format [Microsoft] +

          Open Media Framework + Open Message Format

OMG       Object Management Group

OMI       Open Messaging Interface [Lotus]

OML       Object Manipulation Language

OMNS      Open Network Management System

OMR       Optical Mark Recognition

ONC       Open Network Computing [Sun]

ONDS      Open Network Distribution Services [IBM]

ONE       Open Network Environment [Netscape]

ONU       Optical Network Unit

OOB       Out Of Band

OODB      Object-Oriented Database

OODMS     Object-Oriented Database Management System (also

          see ODBMS)

OOL       Object-Oriented Language

OOOS      Object-Oriented Operating System

OOPL      Object-Oriented Programming Language

OOPS      Object Oriented Programming and Systems

OOS       Object-Oriented Systems +

          Off-line Operating Simulator

OOT       Object-Oriented Technology

OOUI      Object Oriented User Interface

OP        Operation + Optical + Output

OPAC      Online Public Access Catalog [Internet]

OPC       Organic/Optical Photoconductor

OPCODE    Operational Code

OPD       Operand

OPI       Open Prepress Interface

OPM       Operations Per Minute

OPS       Open Profiling Standard + Operations

OPT       Open Protocol Technology

.OPT      Options (file name extension)

OPUS      Octal Program Updating System

OQL       Object Query Language

ORACLE    On-Line Inquiry and Report Generator (UNIX DB program)

ORB       Object Request Broker [Microsoft]

ORDVAC  * Ordnance Variable Automatic Computer

.ORG      Non-Profit Organizations (Domain name) [Internet]

ORI       Online Retrieval Interface

.ORI      Original (file name extension)

OROM      Optical Read-Only Memory

ORS       Output Record Separator

OS        Operating System

OS/2      Operating System/2 [IBM]

OSA       Open Scripting/System Architecture

OSD       Open Software Description/Disribution

OSE       Office Server Extensions [Microsoft]

OS/E      Operating System/Environment

OSF       Open Software Foundation

OSI       Open Systems Interconnection

OSM       Off-Screen Model

OSP       On-Screen Programming + Optical Storage Processor

OSPF      Open Shortest Path First

OSQL      Object Structured Query Language

OSR2      OEM Service Release 2 [Microsoft]

OT        Object Technology

OTA       Operation-Triggered Architecture

OTDR      Optical Time Domain Reflectometer

OTF       Open Token Foundation

OTP       One-Time Programmable

OURS      Open Users Recommended Solutions

.OUT      Outlines (file name extension)

OUTS      Output String

OV        Overflow

OVAL      Object-Based Virtual Application Language [Psion]

.OVL      Program Overlay (file name extension)

.OVR      Program Overlay (file name extension)

OWL       Object/Open Windows Library [Borland]


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P3P       Platform for Privacy Preferences Project

PAB       Personal Address Book

PABX      Private Automatic Branch Exchange

PACE      Priority Access Control Enabled [3Com]

PACS      Picture Archiving and Communication System

PACS-L    Public Access Computer Systems List [Internet]

PAD       Packet Assembler/Disassembler

PADS      Pen Application Development System [Slate Corporation]

PAIH      Public-Access Internet Host [Internet]

PAIS      Public-Access Internet Site [Internet]

.PAK      Packed (compressed file name extension) [NoGate


PAL       Paradox Applications Language [Borland] +

          Phase Alternating Line + Programmed Array Logic +

          Programming Assembly Language

.PAL      Palette (file name extension)

PALC      Plasma-Addressed Liquid Crystal (display)

PALS      Principles of the Alphabet Literacy System

PAM       Pulse Amplitude Modulation

PAN       Personal Area Network [GTE]

PAP       Packet-level Procedure +

          Password Authentication Protocol +

          Printer Access Protocol

PAR       Personal Animation Recorder + Parallel

PARA      Paragraph

PARC      Palo Alto Research Center [XEROX]

PA-RISC   Precision Architecture-RISC [HP]

.PAS      PASCAL source code (file name extension)

PASCAL    (Programming Language named for Blaise Pascal)

.PAT      Patch + Pattern (file name extensions)

PATN      Promotional Port Access Telephone Number

PAX       Portable Archive Exchange [Unix]

PB        Petabyte (1,024 terabytes)

          (One Million Billion characters of information)

PBE       Prompt By Example

PBGA      Plastic Ball Grid Array

PBX       Private Branch Exchange

PC        Personal Computer + Printed Circuit + Program Counter

PCACIAS   Personal Computer Automated Calibration Interval

          Analysis System

PCB       Printed Circuit Board + Program Control Block

PCBC      Plain/Propogating Cipher Block Chaining

PCD       Photo Compact Disk

PC-DOS    Personal Computer - Disk Operating System [IBM]

PCEB      PCI to EISA Bridge [Intel]

PCI       Peripheral Component Interconnect/Interface

PCIC      PC-Card Interrupt Controller

PC-I/O    Program Controlled I/O

PCL       Printer Command Language [HP] + Process Control Language

PCM       Personal Computer Manufacturer +

          Printer Cartridge Metric [HP] +

          Pulse Code Modulation

PCMA      Paired Carrier Multiple Access

PCMC      PCI, Cache, Memory Controller [Intel]

PCMCIA    Personal Computer Memory Card International Association

PCMIM     Personal Computer Media Interface Module

PCN       Personal Computer Network

PCNFS     Personal Computer Network File System

PCO       Point of Control and Observation

PCS       Patchable Control Store +

          Personal Communication Services/System +

          Personal Conferencing Specification +

          Planning Control Sheet + Print Contrast Signal +

          Process Control Systems + Program Counter Store +

          Programmable Drive Table + Project Control System

PCT       Private Communications Technology

.PCT      Picture (file name extension)

.PCX      Picture Image (file name extension)

PD        Phase-Change Dual + Public Domain

PDA       Personal Digital Assistant

PDC       Primary Domain Controller

PDD       Physical Device Driver + Portable Digital Document

PDF       Package Definition File + Portable Document Format +

          Portable Document File + Processor Defined Function +

          Program Development Facility

.PDF      Printer Description (file name extension)[Borland,Lotus]

PDH       Plesiosynchronous Digital Hierarchy

PDIAL     Public Dialup Internet Access List [Internet]

PDL       Page Description Language + Program Description Language

          + Program Design Language

PDM       Product Data Management

PDN       Public Data Network

PDO       Portable Distributed Objects [Next]

PDP       Parallel Data Processing + Plasma Display Panel +

          Programmable Data Processor +

          (DEC Computer System Designation, i.e. PDP-8, PDP-11)

PDS       Packet Driver Specification + Partitioned Data Set +

          Planetary Data System + Portable Document Software +

          Processor Direct Slot [Macintosh]

PDSS      Post Development and Software Support

PDT       Performance Diagnostic Tool [IBM] +

          Programmable Drive Table

PDU       Plug Distribution Unit + Protocol Data Unit

.PDX      Paradox files (file name extension) [Borland] +

          Printer Description Extension (file name extension)

PE        Parity Even + Processing Element + Protect Enable

PEA       Pocket Ethernet Adapter

PEL       Picture Element [IBM]

PEM       Privacy-Enhanced Mail [Internet]

PEN SDK   Pen Computing Software Development Kit

PEP       Packet Exchange Protocol +

          Packetized Ensemble Protocol [Telebit]

PERL      Practical Extraction and Report Language [Unix]

PERT      Program Evaluation and Review Technique

PES       Positioning Error Signal + Processor Enhancement Socket

          Processor Upgrade Socket

PET       Print Enhancement Technology [Compaq]

.PFB      Printer Font Binary (file name extension)

PFE       Programmer's File Editor

.PFM      Printer Font Metrics (file name extension) [Windows]

PFR       Power-Fail Restart

PGA       Pin Grid Array + Professional Graphics Adapter [IBM]

PGC       Program Group Control [Microsoft]

PGDN      Page Down

.PGL      Graphics (file name extension) [Hewlett-Packard]

PGM       Program

PGP       Pretty Good Privacy (name of encryption program)

.PGP      ProGram Parameter (file name extension) [AutoCAD]

PGUP      Page Up

PHIGS     Programmers' Hierarchial Interactive Graphics


.PHO      Phone List (file name extension)

PHS       Personal Handyphone System

PI        Program Interruption

PIA       Peripheral Interface Adapter

PIC       Personal Information Carrier +

          Personal Intelligent Communicator +

          Platform for Internet Content +

          Priority Interrupt Controller +

          Program Interrupt Controller

PICS      Platform for Internet Content Selection

PICT      Picture

PID       Process Identification Number + Product ID +

          Proportional, Integral, Derivative

PIER      Procedures for Internet/Enterprise Renumbering

PIF       Picture Interchange Format File +

          Program Information File

PII       Program Integrated Information

PILOT     Programmed Inquiry Learning Or Teaching

PilotACE* Pilot Automatic Computing Engine

PIM       Personal Information Manager +

          Primary Interface Module +

          Protocol-Independent Multicast

PIN       Personal Identification Number +

          Process Identification Number [Unix]

PINE      Pine Is Not Elm (original usage) +

          Program for Internet News & Email (present usage)

PING      Packet Internet Groper

PIO       Parallel Input/Output + Processor Input/Output +

          Programmed Input/Output

PIP       Picture In Picture + Problem Isolation Procedure +

          Programmable Interconnect Point

PIPO      Parallel In, Parallel Out

PIR       Protocol Independent Routing

PIT       Programmable Interval Timer

PIXEL     Picture Element

PL        Plus

.PL       Pearl Language (file name extension)

PLA       Programmable Logic-Array

PLATO     Programmed Logic for Automatic Teaching Operations

PLC       Programmable Logic Controller

PLCC      Plastic Leadless Chip Carrier

PLD       Programmable Logic Device

PLDS      Pilot Land Data System [NASA]

PLL       Phase Locked Loop

.PLL      Prelinked Library (file name extension) [Clipper]

PL/M      Programming Language for Micros

PLS       Primary Link Station

PLV       Production Level Video

PL/1    * Programming Language One

PM        Presentation Manager [IBM] +

          Preventative Maintenance + Process Manager

P-MAIL    Paper Mail

PMD       Packet Mode Data

PMMU      Paged Memory Management Unit

PMOS      Positive Channel Metal Oxide Semiconductor

PMR       Problem Management Report [IBM]

PMS       Policy Management System

PN        Processing Node

PNA       Programmable Network Access

PNG       Portable Network Graphics

PNNI      Private Network to Network Interface

PNP       Plug And Play

PO        Parity Odd

POC       Point Of Contact

POD       Plain Old Dos

POE       Power Open Environment

POH       Power-On Hours

POL       Problem Oriented Language

POP       Point Of Presence + Pop from Stack +

          Post Office Protocol

POPA      Pop All Registers

POPF      Pop Flags

POR       Power-On-Reset

POS       Point Of Sale + Positive + Programmable Object Select

POSIX     Portable Operating System Interface for Unix

POST      Power-On Self Test

POSTNET   Postal Numeric Encoding Technique (bar code)

POTS      Plain Old Telephone Service

POWER     Performance Optimization with Enhanced RISC [IBM]

PowerPC   Performance Optimization with Enhanced RISC-Performance


PP        Parallel Port

PPA       Pixel Processing Accelerator

.PPD      PostScript Printer Description (file name extension)

PPDS      Personal Printer Data Stream [IBM]

PPGA      Plastic Pin Grid Array

PPI       Precise Pixel Interpolation

PPM       Pages Per Minute

PPP       Point-to-Point Protocol [Internet]

PPS       Packets Per Second + Power Personal Systems [IBM]

PPTP      Point-to-Point Tunneling Protocol [Microsoft]

PQFP      Plastic Quad Flat Pack

PRACSA    Public Remote Access Computer Standards Association

PRAM      Parallel Random-Access Machine +

          Parameter Random Access Memory

.PRD      Printer Driver (file name extension) [Word]

PRE       Preformatted [HTML]

PReP      Power PC Reference Platform [IBM/Motorola]

PRF       Pulse Repetition Frequency

.PRF      Preferences (file name extension) [Grammatik IV]

.PRG      Program (file name extension)

PRI       Primary-Rate Interface

PRINTF    Print with Formatting [C Programming Language]

PRISM     Photo-Refractive Information Storage Material

.PRJ      Project (file name extension) [Borland]

PRMD      Private Mangement Domain [X.400]

PRML      Partial-Response Maximum-Likelihood

.PRO      Profile (file name extension)

PROC      Procedure

PROFS     Professional Office System [IBM]

PROG      Program + Programmer

PROLOG    Programming In Logic (Programming Language)(See HLL)

PROM      Programmable Read Only Memory

PRN       Printer

.PRS      Printer (file name extension) [WordPerfect]

PRTSC     Print Screen

PS        Proportional Spacing

.PS       PostScript (file name extension)

PS/2      Programming System 2 [IBM]

PSAPI     Presentation Space Application Programming Interface

PSC       Personal Super Computer + Print Server Command +

          Product Service Center

PSDN      Packet-Switched Data Network

PSDS      Packet-Switched Data Service

PSERVER   Print Server [NetWare]

PSF       Permanent Swap File

PSID      PostScript Image Data

PSM       Printing Systems Manager

PSN       Packet Switching Network

PSP       Personal Software Products (group) [IBM] +

          Program Segment Prefix

PSPDN     Packet-Switched Public Data Network

P-SRAM    Pseudo-Static Random Access Memory

PSRT      PostScript Round Table [GEnie]

PSTN      Public Switched Telephone Network

PSU       Power Supply Unit

PSW       Program Status Word

.ps.Z     Compressed PostScript (file name extension) [Unix]

PT        Page Table

P/T       Part Time

PTD       Parallel Transfer Disk Drive

PTF       Problem Temporary/Trouble Fix [IBM]

PUB       Public (directory) [Internet] + Publish

.PUB      Publication (file name extension) [Ventura]

PUN       Physical Unit Number

PUP       PARC Universal Packet (protocol)

PUS       Processor Upgrade Socket

PUSHA     Push All Registers

PUSHF     Push Flags

PVC       Permanent Virtual Circuit + Polyvinyl Chloride

PVM       Parallel Virtual Machine +

          Pass-through Virtual Machine (protocol) [IBM]

PVP       Parallel Vector Processing

PVS       Parallel Visualization Server

PW        Password

PWB       Printed Wire Board +

          Programmer's Workbench [Microsoft]

PWD       Print Working Directory [Unix]

PWR       Power

PWSCS     Programmable Workstation Communication Services [IBM]

.PX       Primary Index (file name extension) [Paradox]


| TOP | UP to P | DN to R | BOTTOM |

QA        Quality Assurance

QAM       Quadrature Amplitude Modulation

QBE       Query By Example

QBF       Query by Form

QBIC      Query By Image Content [IBM]

QC        Quality Control

QD        Querty/Dvorak

QDOS      Quick and Dirty Operating System

.QDI      Quicken Dictionary (file name extension) [Intuit]

.QDT      Quicken Data (file name extension) [Intuit]

QEMM      Quarterdeck Expanded Memory Manager [Quarterdeck Corp.]

QFA       Quick File Access

QFE       Quick-Fix Engineering [Microsoft]

QFP       Quad Flat Pack

QIC       Quality Information Using Cycle Time [Hewlett-Packard] +

          Quarter-Inch Cartridge

.QIF      Quicken Import File/Interchange Format

          (file name extension)

.QMT      Quicken Memorized List (file name extension) [Intuit]

.QNX      Quicken Indexes to Data (file name extension) [Intuit]

QOS       Quality Of Service

QPG       Quantum Phase Gate

QPSK      Quadrature Phase Shift Keying

QTC       Quicktime Conferencing [Macintosh]


| TOP | UP to Q | DN to S | BOTTOM |

RA        Return Authorization

.RA       Real Audio (file name extension)

RACF      Resource Access Control Facility

RAD       Rapid Application Development

RADAR     Radio Detection And Ranging +

          Rights, Availabilities, Distribution Analysis

          and Reporting [Disney]

RADB      Routing Arbiter Data Base


RADSL     Rate Adaptive Digital Subscriber Line

RAG       Row Address Generator

RAID      Redundant Arrays of Independent Disks +

          Redundant Arrays of Independent Drives +

          Redundant Arrays of Inexpensive Disks

RAIS      Redundant Arrays of Inexpensive Systems

RALU      Register Arithmetic Logic Unit

RAM       Random Access Memory

.RAM      Real Audio Metafile (file name extension)

RAMDAC    Random Access Memory Digital-to-Analog

          Converter [Sierra]

RAMP      Remote Access Maintenance Protocol [Internet]

RAND      Random

RAP       Rapid Application Prototyping

RARP      Reverse Address Resolution Protocol

RAS       Random Access Storage +

          Reader Admission System [British Library] +

          Reliability, Availability and Serviceability +

          Remote Access Service + Row Address Select

RASAPI    Remote Access Service Application Programming

          Interface [Microsoft]

.RAT      Rating (file name extension)

RAVE      Rendering Acceleration Virtual Engine [Apple Computer]

.RAW      Raw Data (file name extension)

RB        Right Button (of 2 or 3 button Mouse)

RBBS      Remote Bulletin Board System

RBCS      Remote Bar Code System

RBOC      Regional Bell Operating Company

RCL       Rotate Carry Left

RCP       Remote Control Panel + Remote Copy [Internet] +

          Restore Cursor Position

RCPT      Recipient

RCR       Rotate Carry Right

RCS       Records Communications Switching System +

          Revision Control System [Unix]

RD        Receive Data + Remove Directory

R&D       Research and Development

RDA       Remote Database Access

RDB       Receive Data Buffer + Relational Database

RDBMS     Relational Database Management System

RDCLK     Received Timing Clock

RDF       Resource Description Framework [W3C]

RDO       Remote Data Object

RDP       Reliable Datagram Protocol + Remote Desktop Protocol

RDRAM     Rambus DRAM

RDSR      Receiver Data Service Request

RDTO      Receive Data Transfer Offset [IBM]

RDX       Realistic Display Mixer

.REC      Recorder (file name extension) +

          Recreational or Entertainment Activities (Domain

          Name) [Internet]

REC.      Recreation [USENET Newsgroup Category]

.REF      Reference (file name extension)

REG       Register

REGAL     Rigid Epoxy Glass Acrylic Laminate

RELSECT   Relative Sector

REM       Remark + Remote + Ring Error Monitor

REN       Rename

REP       Repeat

REPE      Repeat while Equal

REPNE     Repeat while Not Equal

REPNZ     Repeat while Not Zero

REPZ      Repeat while Zero

REQ       Request

REREG     Re-Register

RES       Remote Execution Service + Reset + Resolution

.RES      Resource (file name extension)

RET       Resolution Enhancement Technology [HP] + Return

RETR      Retrieve

REX       Relocatable Executable

REXEC     Remote Execution

REXX      Restructured Extended Executor (language) [IBM]

RF        Radio Frequency

RFC       Request For Comments [Internet]

RFD       Request for Discussion [Internet]

RFI       Radio Frequency Interference + Request for Information

RFP       Request for Proposal

RFQ       Request for Quotation

RFS       Remote File Sharing + Remote File System

RFT       Revisable Form Text + Rich Text Format

RFU       Reserved For Future Use

RGB       Red-Green-Blue (color model)

RI        Referential Integrity + Ring Indicate

 RID       Relative Identifier

RIFF      Resource Interchange File Format [Microsoft]

RIM       Remote Installation and Maintenance [Microsoft]

RIME      RelayNet International Message Exchange

RIP       Raster Image Processor + Remote Imaging Protocol +

          Routing Information Protocol [Novell]

RIPEM     Riordan's Internet Privacy Enhanced Mail

RIPS      Raster Image Processing System

RISC      Reduced Instruction Set Computing

RIT       Raw Input Thread [Microsoft]

RJE       Remote Job Entry

RLD       Received Line Detect

RLE       Run Length Encoded

RLL       Run Length Limited

RLN       Remote LAN Node [DCA]

RLOGIN    Remote Login

RLSD      Received Line Signal Detected

RLSI    * Ridiculously Large-Scale Integration

RM        Reset Mode

RMA       Return Material Authorization +

          Return to Manufacturer Authorization

RMB       Right Mouse Button

RMDIR     Remove Directory

RMI       Remote Method Invocation [Sun]

RMON      Remote Monitor/Monitoring

RMP       Remote Maintenance Processor [IBM]

RMS       Record Management Services + Root Mean Square

RMW       Read-Modify-Write

RN        Read News [Internet]

RND       Random

RNG       Random Number Generator

RNP       Regional Network Provider

R-O       Read Only

ROB       Reorder Buffer [Intel]

ROL       Rotate Left

ROLAP     Relational On-Line Analytical Processing

ROM       Read Only Memory

ROOM      Real-Time Object-Oriented Modeling

ROP       Raster Operation + RISC Operation

ROR       Rotate Right

ROS       Read-Only Storage [IBM]

ROT       Running Object Table

RPC       Remote Procedure Call

RPG       Report Program Generator (Programming Language)

RPL       Resident Programming Language +

          Requested Privilege Level

RPN       Real Page Number + Reverse Polish Notation

RPRINTER  Remote Printer [NetWare]

RPPROM    Reprogrammable PROM

RPR       Relative Performance Rating

RPT       Repeat

RPQ       Request for Price Quotation

RQBE      Relational Query By Example [Fox Pro]

RR        Real Reality

RS        Radio Shack +

          Recommended Standard (as in RS-232) [EIA] +

          Record Separator + Request to Send

RSA129    (129 digit cryptographic security number named after

          its inventors: Drs. Ronald L. Rivest, Adi Shamir and

          Leonard M. Adleman)

RSAC      Recreational Software Advisory Council

RSCS      Remote Spooling Communications System

RSD       Route Server Daemon

RSH       Remote Shell

RSI       Repetitive Strain Injury (Carpal Tunnel Syndrome)

RSL       Request-and-Status Link

RSP       Required Space Character

RSPX      Remote Sequenced Packet Exchange

RST       Reset + Restart

RSTS      Resource Sharing Time Sharing [Digital]

RSVP      Resource Reservation Protocol

RSX       Realistic Sound Experience +

          Real Time Resource Sharing Executive

RT        Real Time + RISC Technology + Run Time

R/T       Receive/Transmit

RTAM      Remote Terminal Access Method

RTC       Real-Time Clock

RTDM      Real-Time Data Migration

RTEL      Reverse Telnet [Internet]

RTF       Rich Text Format

RTL       Register Transfer Language/Level +

          Resistor Transistor Logic + Right-To-Left +

          Run Time Library

RTM       Response Time Monitor + Runtime Manager [Borland]

RTMP      Routing Table Maintenance Protocol

RTOS      Real-Time Operating System

RTP       Rapid Transport Protocol + Real-Time Protocol

RTS       Remote Takeover System + Request To Send

RTSP      Real-Time Streaming Protocol

RTTI      Runtime Type Information

RTTY      Radio Teletypewriter (Communications)

RTV       Real Time Video

RTX       Run Time Extension

RUN       Rewind/Unload [IBM]

RVA       Relative Virtual Address

RVI       Reverse Interrupt

R/W       Read/Write

RWM       Read-Write Memory

RX        Receiver

RXD       Receive Data


| TOP | UP to R | DN to T | BOTTOM |

SA        Selective Availability

SAA       Systems Application Architecture [IBM]

SAC       Single Attachment Concentrator

SADL      Synchronous Data Link Control [Racal-Vadic]

SAINT   * Symbolic Automatic Integrator

SAL       Shift Arithmetic Left

SAM       Serial Access Memory + Sequential Access Method +

          Security Accounts Manager [Microsoft] +

          Single Application Mode [Microsoft]

SAN       Storage/System Area Network

SANE      Standard Apple Numeric Environment

SAP       Second Audio Program + Service Access Point [DEC] +

          Service Advertising Protocol +

        * Symbolic Assembly Program +

          Systems, Applications and Products (company)

SAPI      Speech Application Program Interface [Microsoft]

SAR       Segmentation and Reassembly +

          Shift Arithmetic Right +

          Successive Approximation Register +

          Synthetic Aperature Radar

SAS       Sales Accounting System + Single Attached Station +

          Single Audio System + Statistical Analysis System

SASI      Shugert Associates System Interface (SCSI originated

          from SASI)

SATAN     Security Administrator Tool for Analyzing Networks

.SAV      Saved (file name extension)

SAVDM     Single Application VDM

SB        Sound Blaster [Creative Labs] + Sound Board

SBA       Scene Balance Algorithms [Kodak]

SBB       Subtract With Borrow

SBC       Single-Board Computer

SBCS      Single-Byte Character Set

SBI       Sound Blaster Instrument

.SBR      Source Browser (file name extension) [Borland]

SBS       Smart Battery Specification [Duracell/Intel]

.SC       Script (file name extension)

SCADA     Supervisory Control and Data Aquisition

SCAM      SCSI Configuration Automatically

SCAS      Scan String

SCB       Subsystem Control Block [IBM]

SCC       Serial Communications Controllers +

          Serial Controller Chip +

          Synchronous Channel Check [IBM]

SCCS      Source Code Control System

SCD       Standard Color Display

S-CDMA    Synchronous Code-Division Multiple Access

SCF       System Control Facility

SCI       Scalable Coherent Interface +

          Serial Communications Interface

SCI.      Science [USENET Newsgroup Category]

SCLM      Softwre Configuration and Library Management [IBM]

SCM       ScreenCam Format [Lotus] +

          Software Configuration Management + Station Class Mark

SCO       Santa Cruz Operation (Software Company)

SCOPE     Simple Communications Programming Environment


SCP       Save Cursor Position + Subsystem Control Port +

          System Control Program

SCR       Silicon Controlled Rectifier

.SCR      Script (file name extension)

SCRN      Screen (video display)

SCRS      Scalable Cluster of RISC Systems

SCSA      Signal Computing System Architecture [Dialogic]

SCSI      Small Computer Systems Interface

SD        Send Data + Super Density

SDA       Software Disk Array + Source Data Automation +

          System Display Architecture [Digital]

SDAM      Single DOS Application Mode

SDB       Symbolic Debugger [Unix]

SDD       Software Description Database [Internet]

SDF       Space Delimited File + Space Delimited Format

.SDF      Standard Data Format (file name extension)

SDH       Synchronous Digital Hieararchy

SDI       Selective Dissemination of Information +

          Single Document Interface

          Software Development Interface [Mosaic]

SDK       Software Developer's Kit [Microsoft]

SDL       Specification and Description Language

SDLC      Synchronous Data Link Control (protocol)

SDM       System Development Multitasking

SDMS      SCSI Device Management System [NCR]

SDN       Software Defined Network [AT&T]

SDNS      Secure Data Network Service

SDR       Streaming Data Request

SDRAM     Synchronous DRAM

SD-ROM    Super Density ROM

SDS       Sysops Distribution System

SDSL      Single-Line/Symmetric Digital Subscriber Line

SD_STB    Streaming Data Strobe [IBM]

SDTV      Standard Definition Television

SDV       Switched Digital Video [AT&T]

SDX       Storage Data Acceleration

SEA       Standard Extended Attribute [OS/2]

.SEA      Self Extracting Archive (file name extension) [Macintosh]

SEAC    * Name of first computer to use transistors, built by

          (National Bureau of) Standards Eastern Automatic

          Calculator (Also see SWAC)

SEAL      Segmentation and Reassembly Layer (protocol) +

          Screening External Access Link [Digital-DEC]

SEC       Single Error Correction

SECAM     Sequentiel Couleur Avec Memoire

          (Sequential Color With Memory)

SECC      Single Edge Contact Cartridge

SED       Stream Editor + Stream-Oriented Editor

SEG       Segment

SEH       Structured Exception Handling

SEL       Select

SEM       Scanning Electron Microscope +

          Standard Electronic Module +

          Strategic Enterprise Management [SAP]

SEPP      Secure Encryption Payment Protocol

SER       Serial

SERCOS    Serial Real-Time Communications System

SET       Secure Electronic Transaction +

          Softwave Engineering Technology

.SET      Driver Set (file name extension) [Lotus 1-2-3] [LDC] +

          Image Settings (file name extension) [Paradox]

SETEXT    Structure Enhanced Text [Internet]

SEU       Smallest Executable Unit

SF        Sign Flag

SFC       System File Checker

SFD       Start Frame Delimiter

SFDR      Spurious-Free Dynamic Range

SFQL      Structured Full-text Query Language

SFS       System File Server

SFT       System Fault Tolerance

SFX       Sound Effect(s)

SGA       Shared Global Area

SGEN      Signal Generator + System Generator

SGDT      Store Global Descriptor Table

SGI       Silicon Graphics, Inc.

SGM       Shaded Graphics Modeling

SGML      Standard Generalized Markup Language

SGR       Set Graphics Rendition

SGRAM     Synchronous Graphics RAM

S/H       Sample and Hold

SHA       Secure Hash Algorithm [NSA]

SHAR      Shell Archive

SHED      Segmented Hypergraphic Editor

SHG       Segmented Hypergraphics

SHL       Shift Logical Left

SHR       Shift Logical Right

S-HTTP    Secure Hypertext Transfer Protocol

SHV       Standard High-Volume

.SHW      Show (file name extension)

SI        Shift-In + Source Index + System Information +

          System Integration

SIC       Standard Industrial Code

SID       Security Identifier + Serial Input Data +

          Station Identification [AT&T] +

          Symbolic Interactive Debugger + System ID

SIDF      System Independent Data Format

SIDH      System Identification for Home Systems

SIDT      Store Interrupt Descriptor Table

SIFT      Stanford Information Filtering Tool

SIG       Special Interest Group

SIGCAT    Special Interest Group on CD-ROM Applications

          and Technology

SIM       Simulator

SIMD      Single Instruction, Multiple Data-stream (processor)

SIMM      Single In-line Memory Module

SIMTEL    Simulation and Teleprocessing

SIMULA    Simulation (language)

SIO       Serial Input/Output (communications driver)

SIP       Single In-line Package

SIPC      Simply Interactive Personal Computer [Microsoft]

SIPO      Serial In, Parallel Out

SIPP      Single In-line Pin Package

SIR       Serial Infrared [Hewlett-Packard]

SIRDS     Single-Image Random Dot Stereogram

SI/SO     Serial In/Serial Out + Shift In/Shift Out

SIT       Special Information Tones

.SIT      Stuff-It (compressed file name extension) [Macintosh]

SIU       System Interface Unit

SKIP      Simple Key-Management for Internet Protocols [Sun]

SKU#      Stock Keeping Unit Number

SLC       Subscriber Line Concentrator

SLDT      Store Local Descriptor Table

SLED      Single Large Expensive Disk

SLIC      System Level Integration Circuit

SLIM      Structured Language for Internet Markup

SLIP      Serial Line Interface Protocol

SLM       Spatial Light Modulator

SLMR      Silly Little Mail Reader

SLOSH     Sea, Lake and Overland Surge from Hurricane (program)

SLP       Service Location Protocol

SLSI      Super Large-Scale Integration

SLSS      Systems Library Subscription Service [IBM]

SLU       Spoken Language Understanding

SM        Set Mode + Shared Memory

SMART     Self-Monitoring Analysis and Reporting Technology

SMB       Server Message Block (protocol) [MII]

SMD       Surface Mounted Device

SMDR      Station Message Detail Recording

SMDS      Switched Multimedia/Multi-Megabit Data Service

SMF       Single Mode Fiber + System Manager Facility [Compaq]

SMI       System Management Interrupt [Intel]

SMIF      Standard Mechanical Interface

SMIL      Synchronized Multimedia Integration Language

S-MIME    Secure MIME

SMIT      System Management Interface Tool [IBM]

SMK       Software Migration Kit [Microsoft]

SML       Standard Meta Language

SMM       System Management Mode [Intel]

SMOBC     Solder Mask Over Bare Copper

SMP       Simple Management Protocol + Symbolic Manipulation

          Program + Symmetrical Multi-Processing +

          Symmetric Multiprocessor

.SMP      Sample (file name extension)

SMPC      Shared Memory Parallel Computer

SMPS      Switching Mode Power Supply

SMRAM     System Management Random Access Memory

SMS       Small Messaging System +

          Storage Management Services [NetWare] +

          Storage Management Subsystem/System +

          Systems Management Server [Microsoft]

SMSW      Store Machine Status Word

SMT       Station Management (protocol) +

          Surface-Mount Technology

SMTP      Simple Mail Transfer Protocol

SMU       System Management Utility

SN        Serial Number

S/N       Signal-to-Noise (Ratio)

SNA       Systems Network Architecture [IBM]

SNAP      Sub-Network Access Protocol

SND       Sound

SNEWS     Secure News Server [Internet]

SNMP      Simple Network Management Protocol

SNOBOL    String Oriented Symbolic Language (Programming Language)

SNP       Serial Number/Password [Omen Technology]

SNR       Signal-to-Noise Ratio

SOA       Start Of Authority

SOC       System On a Chip

SOC.      Social Issues [USENET Newsgroup Category]

SOCKS     Socket Secure (server) [Internet]

SO-DIMM   Small Outline DIMM

SOE       Standard Operating Environment

SOH       Start of Header

SOHO      Small Office/Home Office

SOL       Simulation Oriented Language

SOM       Start of Message + System Object Model [IBM]

SONET     Synchronous Optical Network

SOP       Small Outline Package + Standard Operating Procedures

SOS       Silicon On Sapphire + Sophisticated Operating System +

          Standards and Open Systems

SOTA      State Of The Art

SOX       Sound Exchange

SP        Service Pack [IBM] + Stack Pointer + System Product

SPA       Software Publishers Association

SPAN      Space Physics Analysis Network

SPARC     Scalable Processor Architecture

SPC       Small Peripheral Controller + Statistical Process Control

SPCL      Spectrum Cellular Corporation

SPCS      Stored Program Controlled Switch

SPD       Serial Presence Detect

SPEC      Systems Performance Evaluation Cooperative

SPF       Shortest Path First + System Programming Facility

SPGA      Staggered Pin-Grid Array

SPI       Security Parameters Index + Service Provider Interface +

          SCSI Parallel Interface

SPID      Service Profile/Provider Identifier

SPIKE     Science Planning Intelligent Knowledge-Based

          Environment [STScI]

SPIRES    Stanford Public Information Retrieval System

          [Stanford University]

SPL       Spooler + System Programming Language [HP]

.SPL      Spell Checker (file name extension)

SPLD      Simple Programmable Logic Device

SPM       System Performance Monitor [IBM]

SPOOL     Simultaneous Peripheral Operations On Line

SPOT      Shared Product Object Tree [IBM]

SPP       Sequenced Packet Protocol

SPPS      Scalable Power Parallel System [IBM]

SPR       Special Purpose Register +

          Statistical Pattern Recognition

SPREAD  * Systems Programming, Research, Engineering

          and Development [IBM]

SPS       Shock Protection System + Standby Power System

SPSS      Statistical Package for the Social Sciences

SPT       Sectors Per Track

SPX       Sequenced Packet Exchange [Novell]

SQ        Squeezed (files)

SQE       Signal Quality Error (test)

SQL/DS    Structured Query Language/Data System [IBM]

SQRT      Square Root

SR        Shift Register

SRAM      Shadow Random Access Memory +

          Static Random Access Memory

SRAPI     Speech Recognition API

SRB       Source-Route Bridge

.SRC      Source (file name extension)

SRD       Screen Reader System

SRDRAM    Self-Refreshed DRAM

SRGB      Sustained RGB (values)

SRM       Security Reference Monitor

SRO       Sharable and Read Only

SRP       Suggested Retail Price

.SRP      Script (file name extension)

SRPI      Server-Requester Programming Interface

SRQ       Service Request

SRR       Serially Reusable Resource

SRS       Sound Retrieval System

SS        Stack Segment + Single Sided + Seconds

SSA       Serial Storage Architecture

SSAP      Source Service Access Point

SSCP      Systems Service Control Point [IBM]

SSD       Solid State Disk

SSEC    * Selective Sequence Electronic Calculator [IBM]

SSGA      System Suppport Gate Array

SSH       Secure Shell

SSI       Server Side Includes + Single System Image +

          Small Scale Integration

SSL       Secure Sockets Layer

SSPI      Security Service Provider Interface [Microsoft]

SSRP      Simple Server Redundance Protocol [Cisco]

SST       Spread-Spectrum Technology +

          Systems Services and Technology

STA       Spanning Tree Algorithm

STAR      Self Defining Text Archival

STB       Strobe

STC       Set Carry Flag

STD       Set Direction Flag + Standard

STDA      StreetTalk Directory Assistance [Banyan]

STDAUX    Standard Auxillary

STDERR    Standard Error

STDIN     Standard Input

STDIO.H   Standard Input/Output Header [C Programming Language]

STDM      Statistical Time Division Multiplexer

STDOUT    Standard Output

STDPRN    Standard Printer

STEP      Standard for Exchange of Product

.STF      Structured File (file name extension) [Lotus Agenda]

STI       Set Interrupt Flag

S/TK      Sectors Per Track

STL       Standard Template Library

STN       Super-Twist Nematic

.STORE    Businesses Offering Goods (Domain Name) [Internet]

STOS      Store String

STP       Secure Transfer Protocol + Shielded Twisted Pair (cable) +

          Signal Transfer Point +

          Synchronized Transaction Processing

STR       Store Task Register + Synchronous Transmitter Receiver

STRESS    Structural Engineering System Solver (Programming


STRUDL    Structural Design Language (Programming Language)

STScI     Space Telescope Science Institute

STT       Secure Transaction Technology [Microsoft]

STX       Start of Text

.STY      Style (file name extension) [Ventura, Word, WordPerfect]

SUB       Subroutine + Substitute + Subtract

SUN       Sun Microsystems, Inc.

.SUP      Supplemental Dictionary (file name extension)


SVC       Switched Virtual Circuit

SVF       Simple Vector Format

SVGA      Super Video Graphics Array

S-VHS     Super VHS

SVM       System Virtual Machine [Microsoft]

SVN       Switched Virtual Network [IBM]

SVR       Server

SVR#      System V Release Number [AT&T]

S/W       Software

SWAC    * Mobile version of SEAC, built for deployment to White

          Sands, and named Standards Western Automatic Calculator

SWAIS     Simple Wide Area Information Server [Internet]

SWAP      Shared Wireless Access Protocol

SWISH     Simple Web Indexing System for Humans

SWP       Simple Web Printing

.SWP      Swap (file name extension)

.SYL      Syllabus (file name extension)

SYLK      Symbolic Link

.SYM      Symbols (file name extension)

.SYN      Synonym (file name extension)

SYNC      Synchronous

SYS       System

.SYS      System Configuration (file name extension) +

          System Device Driver (file name extension)

SYSADMIN  System Administrator

SYSGEN    System Generator

SYSLOG    System Log

SYSMOD    System Modification

SYSOP     System Operator

SYSREQ    System Request

SZ        Send ZModem [Unix]