A

A20             Address line 20. The 80286 and higher CPUs allow addresses in 
                real mode to extend slightly beyond the one megabyte mark, 
                which causes an incompatibility with some older programs 
                which expect such addresses to wrap back to the beginning of 
                the address space.  For complete compatibility with the 8088, 
                newer machines thus contain circuitry which permits the 
                twenty-first address line (A20) to be disabled. The CPU then 
                effectively has only twenty address lines in real mode, just
                as the 8088 does, and addresses which would extend beyond the 
                one megabyte mark wrap to the beginning of the address space.  
                See also HMA.
AA        	Auto Answer.
AAB       	All-to-All Broadcast.
AADL            Axiomatic Architecture Description Language.
AAP       	Applications Access Point.
AAP             Association of American Publishers.
AAS       	All-to-All Scatter.
AASP      	ASCII Asynchronous Support Package.
AAT       	Average Access Time.
ABAM            Adaptive Bidirectional Associative Memory.
ABC             Atanasoff-Berry Computer; first special-purpose electronic 
                digital computer, built by John Atanasoff and Clifford Berry
                at Iowa State University in 1942.
ABEND           ABnormal END.
ABI             Application Binary Interface.
ABIOS           Advanced BIOS. The IBM XT/286 and PS/2 models with 80286 or
                higher processors contain two separate BIOSes.  The ABIOS is
                a protected-mode BIOS which is used by OS/2.  For machines
                without an ABIOS, such as the IBM AT, OS/2 loads the
                equivalent of the ABIOS from disk. See also CBIOS.
ABIST     	Automatic Built-In Self-Test.
ABM             Asynchronous Balanced Mode.
ABR       	Available Bit Rate.
ABRS            Automated Book Request System.
ABS       	ABSolute.
ABT       	ABorT.
AC              ACcumulator.
AC              Alternating Current. Electrical current found in a standard 
                wall outlet. Called alternating current because its direction 
                is reversed 60 times per second in the US; 50 times in Europe.
AC        	Automatic Computer.
ACA             Application Control Architecture. DEC's implementation of ORB.
ACC       	ACCumulator.
ACCU            Association of C and C++ Users. The Association of C and C++ 
                Users is a community of people with an interest in the C 
                family of programming languages: K&R C, ANSI C and C++. The 
                community includes professional programmers, the suppliers of 
                compilers, and those who are just interested in the languages.
                ACCU members are using C and C++ on a wide range of platforms 
                - Unix, MS-DOS, OS/2, CP/M - home computers, IBM PCs, 
                workstations and super-computers. Although the organisation is
                based in the UK, the membership is worldwide. There are 
                members in the US, mainland Europe, Russia, the Middle East 
                and Australia. 
ACD       	Automated Call Distribution.
ACD          	Automatic Call Distributor.
ACDI            Asynchronous Communications Device Interface. IBM provides an
                ACDI that provides multitasking asynchronous communications 
                support for OS/2 Extended Edition.
ACE             Adaptive Communication Environment. A C++ wrapper library for
                communications from the University of California at Irvine.
ACE             Advanced Computing Environment.  A consortium to agree on an 
                open architecture based on the MIPS R4000 chip. A computer 
                architecture ARCS will be defined, on which either OS/2 or 
                Open Desktop can be run.
ACE		Adverse Channel Enhancements.
ACE             Asynchronous Communication Element.
ACE             Automatic Calling Equipment.
ACF		Access Control Field.
ACF/NCP         Advanced Communications Function / Network Control Protocol.
                Control programs, such as ACF/NCP control the configurations
                of lines to the controller and perform error recovery.
ACF/VTAM        Advanced Communications Function / Virtual Telecommunications
                Access Method. ACF/VTAM is the most frequently used access
                method in SNA systems. It monitors network performance and
                supports problem determination and analysis based on
                information provided by other SNA components in the network.
ACH       	Automated Clearing House.
ACIAS     	Automated Calibration Interval Analysis System.
ACID            Atomicity, Consistency, Isolation and Durability. Atomic
                transactions should possess several proporties. These are
                often called the ACID proporties, and they should be enforced
                by the concurrency control and recovery methods of the DBMS.
ACIS      	American Committee for Interoperable Systems.
ACIS            Andy, Charles, Ian's System. A solid modelling engine, owned 
                by Spatial Technologies. ACIS is the solid modelling API that 
                most CAD packages now use.
ACK             Acknowledge. A control signal used by the 8255A programmable 
                parallel interface during input and output.
ACL             Access Control List. A list of the services available on a 
                server, each with a list of the hosts permitted to use the 
                service.
ACL             Association for Computational Linguistics. The international 
                scientific and professional society for people working on 
                problems involving natural language and computation. 
                Membership includes the ACL quarterly journal, "Computational
                Linguistics", reduced registration at most ACL-sponsored 
                conferences, discounts on ACL-sponsored publications, and 
                participation in ACL Special Interest Groups. The ACL is in its
                31st year; there are more than 2,000 members worldwide. 
ACL             A Coroutine Language. A Pascal-based implementation of 
                coroutines.
ACM             Access Control Machine. The ACM controls transmission access. 
                The ACM is also responsible for the maintenance of the
                logical ring, including admission of new stations. The third 
                major function of the ACM is to detect and recover, where
                possible, from faults and failures in the token bus network.
ACM             Association for Computer Machinery. 
ACM		Audio Compression Manager.
ACME            A Company that Makes Everything. The canonical imaginary 
                business. Possibly also derived from the word "acme" meaning 
                "highest point". 
ACMS      	Application Control Management System.
ACO             Adaptive Control Optimization.
ACP             Algebra of Communicating Processes.
ACP		Ancillary Control Program.
ACP		Auxillary Control Process.
ACRONYM         Any Compressed Representation Of Nomenclature Yielding 
                Minimization.
ACROSS    	Automated Cargo Release and Operations Service System.
ACS       	Access Control Set.
ACS		Access Control System.
ACS	        Asynchronous Communication Server.
ACSE            Association Control Service Element. A protocol entity 
                forming part of the application layer. It provides the 
                generalized (common) function of establishing and clearing a 
                logical association (connection) between two application 
                entities.
ACTS      	Automated Computer Time Service.
ACTT      	Advanced Communication and Timekeeping Technology.
ACU             Automatic Calling Unit.
AD              Administrative Domain. A collection of hosts and routers, and 
                the interconnecting network(s), managed by a single 
                administrative authority.
ADA       	Automatic Data Acquisitions. Programming Language named after 
		Augusta Ada Lovelace.
ADALINE         ADAptive LINear Element.
ADAM            A DAta Management system. 
ADB             Apple Desktop Bus.
ADC		Adaptive Data Compression protocol.
ADC             Analog to Digital Converter. The ADC scans or samples the
                analog signal at predetermined intervals and converts the
                results of these samples into numeric values.
ADCCP     	Advanced Data Communication Control Procedures.
ADD       	Automatic Document Detection.
ADDD            A Depository of Development Documents. A public domain 
                Software Engineering Environment from GMD developed as part of
                the STONE project.
ADE             Automated Design Engeneering.
.ADF      	Adapter Description File. File name extension.
ADF       	Automatic Document Feeder.
ADI       	AutoCad Device Interface. Driver.
ADL       	Address Data Latch.
ADL             Adventure Definition Language. An adventure game language 
                interpreter designed by Ross Cunniff and Tim Brengle in 1987. 
                ADL is semi-object-oriented with Lisp-like syntax and is a 
                superset of DDL. It is available for Unix, MS-DOS, Amiga and 
                Acorn Archimedes. 
ADL             Ada Development Language. 
ADL             API Definition Language. A project for Automatic Interface 
                Test Generation.
ADLAT     	ADaptive LATtice filter
ADLC      	ADaptive Lossless Data Compression.
ADLC          	Asynchronous Data Link Control.
ADMD      	ADministrative Management Domain.
.ADN      	ADd In utility. File name extension.
ADP             Automatic Data Processing.
ADPCM           Adaptive Digital Pulse Code Modulation. A compression 
                technique used on the Sony minidisk.
ADPS            Automatic Data Processing System.
ADR       	ADdresS.
ADS             Application Development System. With this tool, an
                application developer defines the application functions and
                responses to the distionary. It acts as a prototype tool and 
                enables the user to have an on-line preview of the 
                application.
ADS		Automatic Distribution System.
ADSC      	ADdress Status Changed.
ADSL            Asymmetric Digital Subscriber Loop. A digital 
                telecommunications protocol that tranmsits 6 megabits per
                second over standard phone lines.
ADSM            Automated Data Storage Management.
ADSR            Attack, Decay, Sustain and Release. A generator with four 
		separate stages in the envelop it generates.
ADSU            ATM Data Service Unit.
ADT             Abstract Data Type.  A type whose internal form is hidden 
                behind a set of access functions. Objects of the type are 
                created and inspected only by calls to the access functions. 
                This allows the implementation of the type to be changed 
                without requiring any changes outside the module in which
                it is defined.
AE        	Above or Equal.
AE              Application Entity.
AE              Application Executive.
AEB       	Analog Expansion Bus.
AED             Automated Engineering Design. A systems language for 
                the IBM 7090 and IBM 360 developed at MIT System Laboratory 
                ca. 1965 by a team led by Douglas T. Ross (now at Softech). 
                AED is an extension of ALGOL 60 with records ("plexes"), 
                pointers, and dynamic allocation. DYNAMO II was written in AED,
                as was the first BCPL compiler.
AEIMP           Apple Event Interprocess Messaging Protocol.
AEN             Address-Enable-Line : A bus control line that carries an
                address-enable signal.
AEP             Application Environment Profile. 
AES             Application Environment Specification. A set of specifications
                from OSF for programming and user interfaces, aimed at 
                providing a consistent application environment on different 
                hardware. It includes "O/S" for the operating system
                (user commands and program interfaces), "U/E" for the User 
                Environment (Motif), and "N/S" for Network services.
AESOP           An Evolutionary System for On-line Programming. An early 
                interactive query system on the IBM 1800 using a light pen.
AF        	Auxiliary carry Flag.
AFAIK           As Far As I Know. 
AFC       	Automatic Font Change.
AFC             Automatic Frequency Control.
AFD       	Automatic File Distribution.
AFI             Authority and Format Identifier.
AFII      	Association for Font Information Interchange.
AFIM            AFter IMage. A recovery strategy, known as shadowing, writes
                a new item at a different disk location, so multiple copies
                of a data item can be maintained. In general, the old value
                of the data item before updating is called the BFIM, and the
                new value after updating is called the AFIM. See also BFIM.
AFIPS           American Federation of Information Processing Societies. 
AFIS      	Automated Fingerprint Identification System.
AFJ             April Fool's Joke. Elaborate April Fool's hoaxes are a 
                long-established tradition on Usenet and Internet. In fact, 
                April Fool's Day is the *only* seasonal holiday marked by 
                customary observances on the hacker networks.
AFK             Away From Keyboard. 
.AFM      	Adobe Font Metrics. File name extension. Adobe Systems.
AFNOR           Association Francaise pour la NORmalisation. The French 
                national standards institute, a member of ISO.
AFP             Apple File Protocol.
AFP             Appletalk Filing Protocol. 
AFS             Andrew File System. The distributed file system of the Andrew 
                Project, adopted by the OSF as part of their Distributed 
                Computing Environment.
AFTP      	Anonymous File Transfer Protocol.
AG              Address Generation.
AGC       	Automatic Gain Control.
AGEX            Address Generation/EXecute cycle.
AGL             Apple's Graphics Library.
AGL             Atelier de Genie Logiciel. French for IPSE.
AGM             Alchourron, Gardenfors and Makinson.
AGU             Address-Generation Unit.
AHDL            Analog Hardware Design Language. A language under development 
                by the US Air Force.
AHPL            A Hardware Programming Language. A register-level language by 
                Hill and Peterson, some of whose operators resemble APL.
AI		Analog Input.
AI              Artificial Intelligence. The subfield of computer science 
                concerned with the concepts and methods of symbolic inference 
                by computer and symbolic knowledge representation for use in 
                making inferences. AI can be seen as an attempt to model 
                aspects of human thought on computers. It is also sometimes 
                defined as trying to solve by computer any problem that a 
                human can solve faster.
AIA             Application Integration Architecture. DEC's "open standards" 
                specifications.
AIC       	AIXwindows Interface Composer.
AID             Algebraic Interpretive Dialogue. A version of Joss II for the 
                PDP-10.
AIDS            A* Infected Disk Syndrome ("A*" is a glob pattern that matches,
                but is not limited to, Apple Computer), this condition is 
                quite often the result of practicing unsafe SEX.
AIF       	Audio Interchange Format.
AIFF            Audio Interchange File Format.  A format developed by Apple 
                Computer Inc. for storing high-quality sampled audio and 
                musical instrument information. It is also used by SGI and 
                several professional audio packages.
AIIM            Association for Information and Image Management.
AIMACO          AIr MAterial COmmand compiler. A modification of FLOW-MATIC. 
                AIMACO was supplanted by COBOL.
AIN       	Advanced Intelligent Network.
AISB      	Association of Imaging Service Bureaus.
AISP      	Association of Information Systems Professionals.
AITCW           Abbreviations In The Computer World. A list of common used
                acronyms, shorts for company names, ... .
AIX             Advanced Interactive eXecutive. IBM's version of Unix, taken 
                as the basis for the OSF standard.
AIX             AIn't Unix.
AKC             Ascending Kleene Chain. 
AKCL            Austin Kyoto Common Lisp. A collection of ports, bug fixes, and
                performance improvements to KCL by William Schelter, University
                of Texas.
AKL             Andorra Kernel Language. The successor to KAP. A prototype 
                implementation is available from the author, S. Janson.
AL              Analog Loopback. See RDL, LDL.
AL              Artificial Life.  The study of synthetic systems which behave 
                like natural living systems in some way. Artificial Life 
                complements the traditional biological sciences concerned with
                the analysis of living organisms by attempting to create 
                lifelike behaviours within computers and other artificial 
                media. Artificial Life can contribute to theoretical biology 
                by modelling forms of life other than those which exist in 
                nature. It has applications in environmental and financial 
                modelling and network communications.
AL              Assembly Language. A language for industrial robots developed 
                at Stanford University in the 1970s.
AL              The low byte in the A register of the 8088 microprocessor.
ALADIN          A Language for Attributed DefINitions. A language for formal 
                specification of attributed grammars. ALADIN is the input 
                language for the GAG compiler generator. It is applicative and
                strongly typed.
ALC             Assembly Language Compiler. An alternative name for IBM 360 
                assembly language.
ALC		Arithmetic and Logic Circuits.
ALC		Automatic Level Control.
ALD             Automated Logic Diagram.
ALDES           ALgorithm DEScription.
ALDiSP          Applicative Language for DIgital Signal Processing. A 
                functional language with special features for real-time I/O 
                and numerical processing, developed at the Technical 
                University of Berlin in 1989.
ALE       	Address Latch Enable.
ALEC            A Language with an Extensible Compiler. A language Implemented
                using RCC on an ICL 1906A.
ALEPH           A Language Encouraging Program Hierarchy. 
ALF             Algebraic Logic Functional language. A language by Rudolf 
                Opalla which combines functional programming and logic 
                programming techniques. ALF is based on Horn clause logic with
                equality which consists of predicates and Horn clauses for
                logic programming, and functions and equations for functional 
                programming. Any functional expression can be used in a goal 
                literal and arbitrary predicates can occur in conditions of 
                equations. ALF uses narrowing and rewriting.
ALFL            A Lazy Function Language. A weakly typed, lazy functional 
                language developed by Paul Hudak of Yale in 1983. Alfl is 
                implemented as a Scheme preprocessor for the Orbit compiler,
                by transforming laziness into force-and-delay.
ALGOL 58        ALGOrithmic Language 1958. An early version of ALGOL 60, 
                originally known as "IAL".
ALGOL 60        ALGOrithmic Language 1960. A portable language for scientific 
                computations. ALGOL 60 was small and elegant. It was 
                block-structured, nested, recursive, and free form. It was 
                also the first language to be described in BNF. There were 
                three lexical representations: hardware, reference, and 
                publication. The only structured data types were arrays, but 
                they were permitted to have lower bounds and could be dynamic. 
                It also had conditional expressions; it introduced :=; 
                if-then-else; very general "for" loops; switch declaration 
                (an array of statement labels generalising FORTRAN's computed 
                goto). Parameters were call-by-name and call-by-value. It had 
                static local "own" variables. It lacked user-defined types, 
                character manipulation and standard I/O.
ALGOL 68        ALGOrithmic Language 1968. An extensive revision of ALGOL 60 
                by Adriaan van Wijngaarden et al. ALGOL 68 was discussed from 
                1963 by Working Group 2.1 of IFIP. It's definition was 
                accepted in December 1968. ALGOL 68 was complex, and posed 
                difficulties for both implementors and users. It featured
                structural equivalence; automatic type conversion ("cooercion")
                including dereferencing; flexible arrays; generalised loops 
                (for-from-by-to-while-do-od), if-then-elif-fi, an integer case
                statement with an 'out' clause; skip and goto statements; 
                blocks; procedures; user-defined operators; procedure 
                parameters; concurrent execution (cobegin/coend); semaphores; 
                generators "heap" and "loc" for dynamic allocation. It had no 
                abstract data types or separate compilation.
ALI             Array Level Interface.
ALIAS           ALgorIthmic ASsembly language. Machine oriented language, a 
                variant of BLISS. Implemented in BCPL for the PDP9.
ALIBI     	Adaptive Location of Internetworked Bases of Information.
ALIWEB    	Archie Like Indexing in the Web.
ALM             Assembly Language for Multics.
ALP             A List-Processing extension of Mercury Autocode.
ALR       	Advanced Logic Research, Inc.
ALT       	ALTernate.
Altair 8800     One of the first personal computers, introduced in kit form
                in 1974 by Micro Instrumentation and Technology Systems
                (MITS); used an Intel 8080 microprocessor.
ALU             Arithmetic and Logic Unit. he part of the central processing 
                unit which performs operations such as addition, subtraction 
                and multiplication of integers and bit-wise AND, OR, NOT, XOR 
                and other Boolean operations. The CPU's instruction decode 
                logic determines which particular operation the ALU should 
                perform, the source the operands and the destination of the 
                result. The width in bits of the words which the ALU handles 
                is usually the same as that quoted for the processor as a whole
                whereas its external busses may be narrower. Floating-point 
                operations are usually done be a separate 
                "floating-point unit". Some processors use the ALU for address
                calculations (eg. incrementing the program counter), others 
                have separate logic for this.
ALU             Association of Lisp Users. 
ALS             Automatic Line Switching. A feature that allows the power 
                supply to operate from either 120, or 220 to 240 volts AC 
                input line without intervention by the operator.
AM              Amplitude Modulation. A modulation technique used to allow 
                data to be transmitted across an analogue network, such as a 
                switched telephone network. The amplitude of a single 
                (carrier) frequency is varied (modulated) between two levels- 
                one for binary 0 and the other for binary 1.
AMANDDA   	Automated Messaging AND Directory Assistance.
AMBIT           Algebraic Manipulation By Identity Translation (also claimed:
                "Acronym May Be Ignored Totally"). An early pattern-matching 
                language, developed by C. Christensen of Massachusetts Computer
                Assocs in 1964, aimed at algebraic manipulation.
AMBIT/G         Algebraic Manipulation By Identity Translation for Graphs.
AMBIT/L         Algebraic Manipulation By Identity Translation for Lists. A 
                variant of AMBIT supporting list handling and pattern matching
                rules based on two-dimensional diagrams.
AMBIT/S         Algebraic Manipulation By Identity Translation for Strings.
AMD		Active Matrix Display.
AMD             Advanced Micro Devices. The fifth-largest, US manufacturer of 
                integrated circuits, founded in 1969. AMD focusses on the 
                personal and networked computation and communications market. 
                They produce microprocessors, embedded processors and related 
                peripherals, memories, programmable logic devices, circuits 
                for telecommuncations and networking applications.
AML             A Manufacturing Language.
AML/E           A Manufacturing Language Entry. Simple version of AML, 
                implemented on PC, with graphic display of the robot position.
AMLCD           Active-Matrix Liquid-Crystal Display.
AMMA      	Advanced Memory Management Architecture.
AMN             Abstract Machine Notation. A language for specifying Abstract 
                Machines in the B-Method, based on the mathematical theory of 
                Generalised Substitutions.
AMP             Algebraic Manipulation Package. A symbolic mathematics program
                written in Modula-2, seen on CompuServe.
AMPPL-II        Associative Memory Parallel Processing Language. Early 70's.
AMPS      	Advanced Mobile Phone Service.
AMS             Andrew Message System. A multimedia interface to electronic 
                mail and bulletin boards, developed as part of the Andrew
                Project. 
AMSC            American Mobile Satellite Corp.
AMTRAN          Automatic Mathematical TRANslation. NASA Huntsville, 1966. For
                IBM 1620, based on Culler-Fried System, requires special 
                terminal.
ANCOVA    	ANalysis of COVAriance
ANDF            Architecture Neutral Distribution Format. ANDF is a VBI that 
                was developed by the U.K Defence Research Agency. It's 
                intended to be used to distribute software so that it will 
                run on any of the OMI target processors.
ANI       	Automatic Number Identification.
ANL             Argonne National Laboratory. 
.ANN      	ANNotations. File name extension.
ANNA            ANNotated Ada. A specification language developed at Stanford 
                University ca. 1980 for formally specifying Ada programs. It 
                has a Specification Analyzer and a Consistency Checking System.
                It adds semantic assertions in the form of Ada comments.
ANOVA     	ANalysis Of VAriance.
ANS             Advanced Network & Services.
ANSA            Advanced Network Systems Architecture: a "software bus" based 
                on a model for distributed systems developed as an Esprit 
                project.
ANSI            American National Standards Institute. This a national 
                standards organization comprised of members from computer 
                manufacturers and users in the United States. It is also the 
                US member body of ISO. Its members are involved in the 
                development of standards at all levels in the ISO Reference 
                Model.
ANT             Applied Network Technology.
ANTLR           ANother Tool for Language Recognition. The parser generator in
                the Purdue Compiler-Construction Tool Set.
ANU             Australian National University. 
AO        	Analog Output.
AOC             Automated Operator Console.
AOCE            Apple Open Collaboration Environment. Software for electronic 
                mail and directory services.
AOE       	Application Operating Environment.
AOIV            Automatically Operated Inlet Valve.
AOL             America On-Line. A US on-line service provider based in Vienna,
                Virginia, USA. AOL claims to be the largest and fastest growing
                provider of online services in the world, with the most active
                subscriber base. AOL offers its three million subscribers 
                electronic mail, interactive newspapers and magazines, 
                conferencing, software libraries, computing support, and online
                classes.
AOS             A PDP-10 instruction that took any memory location and added 1
                to it. AOS meant "Add One and do not Skip". Why, you may ask, 
                does the "S" stand for "do not Skip" rather than for "Skip"? 
                Ah, here was a beloved piece of PDP-10 folklore. There were 
                eight such instructions: AOSE added 1 and then skipped the next
                instruction if the result was Equal to zero; AOSG added 1 and 
                then skipped if the result was Greater than 0; AOSN added 1 
                and then skipped if the result was Not 0; AOSA added 1 and 
                then skipped Always; and so on. Just plain AOS didn't say when
                to skip, so it never skipped.
AOSP            Automatic Operating and Scheduling Program. It was the
                up-to-data operating system of a commercial multiprocessor,
                the Burroughs D825.
AP		Adjunct Processor.
AP              Application Proces.
APA       	Adaptive Packet Assembly. 
APA          	All Points Addressable.
APA             Application Portability Architecture.
APA		Arithmetic Processing Accelerator.
APAL            Array Processor Assembly Language. The assembly language for 
                the DAP parallel computer.
APAR      	Authorized Program Analysis Report.
APAREL          A PArse REquest Language. PL/I extension to provide BNF 
                parsing routines, for IBM 360.
APAREN    	Address PARity ENable.
APC             Association for Progressive Communications. 
APCUG     	Association of PC User Groups.
APDL            Algorithmic Processor Description Language. ALGOL 60-like 
                language for describing computer design, for CDC G-21. 
APDU            Application Protocol Data Units. A packet of data exchanged 
                between two application programs across a network. This is
                the highest level view of communication in the OSI seven layer
                model and a single packet exchanged at this level may actually
                be transmitted as several packets at a lower layer as well as 
                having extra information (headers) added for routing etc.
API             Application Program[ming] Interface. The defined set of calls
                which a program may make to interact with or request services 
                of the operating system or environment under which it is 
                running.  Because the inputs and outputs of the calls are 
                well-defined, a program using the API can continue using the
                identical calls even if the internal organization of the 
                program providing the API changes.
APIC      	Advanced Programmable Interrupt Controller.
APL             A Programming Language. An interactive, mathematically-
                oriented language which is well-suited to manipulating 
                matrices. Originally using Greek letters and numerous special
                symbols, thus requiring a special display, versions are now 
                available which use keywords in place of the special symbols.
APM             Advanced Power Management.A system specification that reduces 
                power consumption of the computer by turning off the 
                microprocessor and other components when applications are 
                idle and between keystrokes. 
.APP      	APPlication. File name extension.
APPC            Advanced Program-to-Program Communicqtions. The express purpose
                of APPC is to provide a single stategic LU type for all IBM 
                products that support distributed processing.
APPI      	Advanced Peer-to-Peer Internetworking.
Apple II        An early (circa 1977) 8-bit microcomputer by Apple 
                Corporation based on MOS Technology 6502 microprocessor.
                Apple Macintosh See Macintosh.
APPN            Avanced Peer-to-Peer Networking. = SNA. IBM data communications
                support that routes data in a network between two or more APPC
                systems that need not be adjacent.
APPS            APPlication Server.
APS       	Asynchronous Protocol Specification.
APSE            Ada Programming Support Environment. 
APT       	Address Pass Through.
APT		Advanced Parallel Technology.
APT             Automatically Programmed Tools. A language for numerically 
                controlled machine tools.
AR              Argument Register : Within an associative memory, the
                register that holds the argument for an associative search.
ARA       	Apple Remote Access.
ARAG      	Antireflective-Antiglare.
ARAS      	Antireflective-Antistatic.
ARB             Address Reorder Buffer.
ARC             Advanced RISC Computing specification. The baseline hardware 
                requirements for an ACE-compatible system.
.ARC      	ARChive. File name extension.
ARCA      	Advanced RISC Computing Architecture.
ARCnet    	Attached Resource Computer NETwork.
ARCS            Advanced RISC Computing Specification. See ARC.
ARD             Allcache Routing and Directory cell.
.ARJ		ARchieve Jung. File name extension. Written by Robert K. Jung.
ARL       	Adjusted Ring Length.
ARL             ASSET Reuse Library. 
ARLL      	Advanced Run Length Limited.
ARM             Advanced RISC Machine. A series of low-cost, power-efficient 
                32-bit RISC microprocessors for embedded control, computing, 
                digital signal processing, games, consumer multimedia and 
                portable applications. It was the first commercial RISC 
                microprocessor and is currently licensed for production by 
                Asahi Kasei Microsystems, Cirrus Logic, GEC Plessey
                Semiconductors, Samsung, Sharp, Texas Instruments and VLSI 
                Technology.
ARM             Advanced RISC Machines Ltd. A company formed in 1990 by Acorn 
                Computers Ltd., Apple Computer Inc. and VLSI Technology to 
                market and develop the Advanced RISC Machine microprocessor 
                family, originally designed by Acorn.
ARM          	Annotated Reference Manual.
ARM          	Asynchronous Response Mode.
ARMA      	Association of Records Managers and Administrators.
ARMM            Automated Retroactive Minimal Moderation. A Usenet robot 
                created by Dick Depew of Munroe Falls, Ohio. ARMM was intended
                to automatically cancel posts from anonymous-posting sites. 
                Unfortunately, the robot's recogniser for anonymous postings 
                triggered on its own automatically-generated control messages!
                Transformed by this stroke of programming ineptitude into a 
                monster of Frankensteinian proportions, it broke loose on the 
                night of March 31, 1993 and proceeded to spam news.admin.policy
                with a recursive explosion of over 200 messages.
ARP             Address Resolution Protocol. The ARP is used to map the
                32-bit IP address to an Ethernet 48-bit address.
ARPA            Advanced Research Projects Agency. The former name of the US 
                government agency that funded the creation of the ARPANET and 
                later the Internet- now DARPA.
ARPANET         Advanced Research Projects Agency NETwork. A pioneering 
                longhaul wide area network funded by ARPA. It became 
                operational in 1968 and served as the basis for early 
                networking research, as well as a central backbone during the 
                development of the Internet. The ARPANET consisted of 
                individual packet switching computers interconnected by leased
                lines. Protocols used include FTP and telnet. It has now been 
                replaced by NSFnet.
ARPL      	Adjust Requested Privilege Level.
ARQ             Automatic Repeat Request. A general term for error control
                protocols which feature error detection and automatic
                retransmission of detective blocks of data.
ARTIC     	A Real-Time Interface Compressor.
ARTS            Asynchronous Remote Taleover Server. The PC that supports
                remote takeover is sometimes called an ARTS. The ARTS
                software nomally runs in hidden, background mode on the
                remote PC and supports asynchronous communications with, and
                complete takeover, of operation from a remote PC. See also
                ARTT.
ARTT            Asynchronous Remote Takeover Terminal. The PC that performs
                the remote takeover must execute an ARTT version of the same
                software as the ARTS in a foreground mode. See also ARTS.
ARU       	Audio Response Unit.
AS		Authentication Server.
AS              Autonomous System. A collection of routers under a single 
                administrative authority using a common Interior Gateway 
                Protocol for routing packets.
AS3AP     	ANSI SQL Standard Scalable and Portable.
ASA             Adaptive Simulated Annealing. A language interface to a neural
                net simulator(?) by Lester Ingber.
ASAP      	As Soon As Possible.
ASAP          	Automatic Switching And Processing.
.ASC		ASCII text. File name extension.
ASC             See TI ASC.
ASCII           American Standard Code for Information Interchange. A 7-bit
                code that maps binary values into characters and control
                codes.
ASCIZ           A NULL-terminated ASCII string.  The ASCIZ string "ABC"
                consists of the four bytes 41h, 42h, 43h, and 00h.
ASDIMPL         ASDo IMPLementation Language. A C-like language, run on 
                Burroughs' mainframe computers in the early 80's, and 
                cross-compiled to x86-based embedded processors.
ASDL            Abstract-type and Scheme-Definition Language. A language 
                developed as part of Esprit project GRASPIN, as a basis for 
                generating language-based editors and environments. It 
                combines an object-oriented type system, syntax-directed 
                translation schemes and a target-language interface.
ASE             Advanced Software Environment. An object-oriented application 
                support system from Nixdorf.
ASE             Application Service Element. Software in the presentation layer
                of the OSI seven layer model which provides an abstracted
                interface layer to service application protocol data units 
                (APDU). Because applications and networks vary, ASEs are split 
                into common services and specific services.
ASF             Algebraic Specification Language. A language for equational 
                specification of abstract data types.
ASF             Automatic System Facility. A menu driven front end to the
                system that permits a set of form-based functions to define
                and manipulate relational views in the form of logical
                records.
ASIC            Application Specific Integration Circuit. An integrated circuit
                designed to perform a particular function by defining the 
                interconnection of a set of basic circuit building blocks 
                drawn from a library provided by the circuit manufacturer.
ASIS            Ada Semantic Interface Specification. An intermediate 
                representation for Ada.
ASIS            Application Software Installation Server. 
ASIT      	Advanced Security and Identification Technology.
ASK             Amplitude Shift Keying. 
ASL             Adaptive Speed Leveling. ASL keeps the modem online, always
                operating at the highest possible speed, and constantly
                ensuring data integrity.
ASL             Algebraic Specification Language.
ASLM            Apple Shared Library Manager.
.ASM      	ASseMbler source language. File name extension.
ASME            American Society of Mechanical Engineers. A group involved in 
                CAD standardisation.
ASN             Autonomous System Number. Used for routing on Internet.
ASN.1           Abstract Syntax Notation One. An abstract syntax used to 
                define the structure of the protocol data units associated 
                with a particular protocol entity.
ASP       	Association of Shareware Professionals.
ASPI      	Advanced SCSI Programming Interface. First introduced by
		Adaptec.
ASPOL           A Simulation Process-Oriented Language. An ALGOL-like language 
                for computer simulation.
ASPS      	Advanced Signal Processing System.
ASQC            American Society for Quality Control. 
ASR       	Address Space Register.
ASR		Automatic Send-Receive.
ASR          	Automatic Speech Recognition.
ASSET           Asset Source for Software Engineering Technology. A program to
                promote software reuse by the US DoD.
AST       	AST Research, Inc. (named from first initials of the
          	founders: Albert Wong, Safi Qureshey, Thomas Yuen)
ASTAP           Advanced STatistical Analysis Program. Analysing electronic 
                circuits and other networks.
Astral          Alliance for Strategic Token Ring Advancement and Leadership.
ASYNC     	ASYNChronous.
AT              Advanced Technology; refers to the IBM PC AT and its clones.
ATA             Advanced Technology Attachment. A disk drive interface 
                standard. See also IDE.
ATA DTD         American Transportation Association Document Type Definition.
Atari           A low-cost 6502-based personal computer.
ATDP      	Attention Dial Pulse.
ATDT      	Attention Dial Tone.
ATE       	Automated Test Equipment.
ATF             Automatic Track Finding.
AtFS            ATtributed File System. The basis of the Shape_VC toolkit. 
                Cooperative work within projects is supported by a status model
                controlling visibility of version objects, locking, and "long 
                transactions" for synchronizing concurrent updates. The concept
                of object attributes provides a basis for storing 
                management information with versions and passing this 
                information between individual tools. This mechanism is useful 
                for building integrated environments from a set of unrelated 
                tools.
ATG       	Advanced Technology Group.
ATH       	Attention Hang-Up.
ATIS            A Tools Integration Standard.
ATK             The Andrew Toolkit.
ATLAS           Abbreviated Test Language for Avionics Systems. MIL-spec 
                language for automatic testing of avionics equipment. 
                Replaced/upgraded Gaelic and several other test languages.
ATM             Adobe Type Manager. Software that produces PostScript {outline
                fonts on screen and paper. There are versions that run under
                Microsoft Windows and on the Macintosh.
ATM             Asynchronous Transfer Mode. The proposed mode of operation of 
                the emerging broadband integrated services digital network. 
                All information to be transmitted - voice, data, image, video 
                - is first fragmented into small, fixed-sized frames known as 
                cells. These are then switched and routed using packet 
                switching principles - also known as cell or post-packet 
                switching.
ATM             Automatic Teller Machine. A cash dispenser.
ATOLL           Acceptance, Test Or Launch Language. Language used for 
                automating the checkout and launch of Saturn rockets.
ATP             AppleTalk Protocol.
ATPS      	AppleTalk Printing Services.
ATR       	Automatic Terminal Recognition.
ATS       	Administrative Terminal System.
ATS          	Apple Terminal Services.
ATS             Attribute Translation System. A BNF-based parser generator from
                the University of Saskatchewan(?). It generates table-driven 
                LL parsers with full insert-only error recovery. It also has 
                full left-attribute semantic handling, which is a dream 
                compared to using YACC's parser actions.
AT&T            American Telephone and Telegraph Inc. One of the largest US 
                telecommunications providers. Also noted for being the 
                birthplace of the Unix operating system and the C and C++ 
                programming languages.
ATTN      	ATTentioN.
ATTRIB    	ATTRIBute. See also ATR.
ATZ       	ATtention Restore configuration profile from nonvolatile RAM.
.AU       	AUdio. File name extension.
AUDIT     	Automated Data Input Terminal.
AUI             Adaptable User Interface. A toolkit from Oracle allowing 
                applications to be written portably for different windowing 
                systems. It provides one call level interface along with a 
                resource manager and editor across a range of "standard" GUIs,
                including Macintosh, Microsoft Windows and the X Window System.
AUI             Attachment Unit Interface. The cable, connectors, and
                transmission circuitry used to interconnect the PLS sublayer
                and MAU.
AUP             Acceptable Use Policy. Rules applied by many transit networks 
                which restrict the use to which the network may be put. A well
                known example is NSFNet which does not allow commercial use.
                Enforcement of AUPs varies with the network.
AUTO		AUTOmatic.
AUTODIN         AUTOmatic DIgital Network.
AUTOEXEC  	AUTOmatic EXECution
AUTOGRP         AUTOmated GRouPing system. An interactive statistical analysis
                system, an extension of CML.
AUX       	AUXiliary.
AV              Audio-Video.
AVA       	Audio Visual Authoring.
AVATAR          Advanced Video Attribute Terminal Assembler and Recreator. A
                set of control codes which may be used to affect the output
                of characters to the screen on systems equipped with an
                appropriate driver.  Similar in intent to ANSI sequences,
                AVATAR has shorter command sequences and provides additional
                PC-specific functionality. AVATAR is primarily used by the
                Opus and Maximus bulletin board systems (it was designed by
                one of the developers of the Opus system).
AVC       	Audio Visual Connection.
AVG       	AVeraGe.
AVI             Audio Video Interleave.
AVL             Adelson-Velskii and Landis. An AVL-tree will be said to be
                balanced if and only if, for every node, the difference in
                height of its two subtrees is at most 1.
AVR       	Automatic Voice Recognition.
AVS             Application Visualisation System. A portable, modular, 
                Unix-based graphics package supported by a consortium of 
                vendors including Convex, DEC, IBM, HP, SET Technologies, 
                Stardent and WaveTracer.
AWG       	American Wire Gage.
AWK             Aho, Weinberger and Kernighan. An interpreted language for 
                massaging text data developed by Alfred Aho, Peter Weinberger,
                and Brian Kernighan in 1978. It is characterised by C-like 
                syntax, declaration-free variables, associative arrays, and 
                field-oriented text processing.
AWS       	Advanced Workstations and Systems group.
AX              Accumulator register of the 8088 microprocessor.
AX		Architecture eXtended.
AYT             Are You There ?

