D

D2C		Decimal To Character.
D2T2		Dye Diffusion Thermal Transfer printing.
D2X		Decimal To heXadecimal.
DA              Design Automation.
DA              Device Adapter.
D/A		Digital to Analog.
DAA		Data Access Arrangement.
DAA		Decimal Adjust for Addition.
DAC		Data Acquisition and Control.
DAC		Data Authentication Code.
DAC             Digital-to-Analog Converter. A hardware device (in its
                simplest form, nothing more than a set of interconnected
                resistors) which converts a digital number into an analog
                signal whose voltage is proportional to the value of the
                digital number.  VGA and later color video boards use DACs to
                convert color values into the analog signals sent to the
                display; sound boards normally use DACs as well. See also ADC.
DACKn           DMA acknowledge line n.
DACS            DAtaset Catalog System.
DAD             Desktop Application Director.
DAI		Distributed Artificial Intelligence.
DAL		Data Access Language.
DAL		Disk Access Lockout.
DAM		Data Acquisition and Monitoring.
DAO		Data Access Object.
DAP		Data Access Protocol.
DAP		Developer Assistance Program.
DAP             Distributed Array Processor. It predates the MPP and consists
                of a 64 x 64 array of bit-serial processors, each with
                4 Kbits of memory and a clock cycle of 200 nanoseconds.
DAQ             Data AcQuisition.
DARI		Database Application Remote Interface.
DARPA           Defence Advanced Research Projects Agency. See ARPA.
DAS		Decimal Adjust for Subtraction.
DAS		Dual-Attached Station.
DASD		Direct Access Storage Device.
DASH            Directory Architecture for SHared memory. The Stanford DASH
                project is exploring the feasibility for large-scale
                shared-memory computers with hardware cache coherence.
.DAT		Data. File name extension.
DAT             Digital AudioTape.
DAT		Disk Array Technology.
DAT             Dynamic Address Translation.
DATACOM		DATA COMmunications.
DAV             Digital Audio-Video.
dB		Decibel.
DB		DataBase.
DB		Data Buffer.
DB2             IBMs Database management system.
DB-25           A 25-pin connector commonly used in the United States as the
                connector of choice for the RS-232-C seriel interface
                standard.
DB-9            The standard IBM serial port for the AT is a DB-9 male
                connector.
dBA       	Adjusted Decibel.
DBA             DataBase Administrator. The DBA is responsible for
                authorizing access to the database, for coordinating and
                monitoring its use and for acquiring software and hardware
                resources as needed.
DBACTRL         DataBase ConTRoL. DBACTRL privilege on a specific database is
                similar to DBADM except that only control operations and no
                data manipulation operations are allowed.
DBADM           DataBase ADMinistrator. DBADM priviledge on a specific
                database allows the holder to execute any operation on that
                database.
DBCS		Double-Byte Character Set.
DBD             DataBase Description. For a given installation, the data in
                the database comprises several physical databases. Each
                physical database has a data definition.
DB/DC           DataBase / Data Communications. The DBMS needs to interface
                with communications software, whose function is to allow
                users a locations remote from the database system site to
                access the database through computer terminals, workstations
                or their local micro- or minicomputers. These are connected
                to the database site through data communications hardware
                such as phone lines, long-haul networks or satellite
                communication devices.
.DBF		DataBase File. File name extension.
DBI             DataBase Implementor.
DBM		DataBase Manager.
DBMAINT         DataBase MAINTenance. DBMAINT priviledge on a specific
                database allows the holder to execute read-only maintenance
                operations (such as backup) on the database.
DBMS            DataBase Management System. A DBMS is collection of programs
                that enables users to create and maintain a database.
DBPL            DataBase Programming Language.This language will minimize the
                "impedance mismatch" among traditional programming languages
                and database query languages.
DBRM            DataBase Request Modules. They are a collection of SQL
                statements in a parse tree form input to the bind process.
DBS             DataBase System. Database + software = DBS.
DBTG            Data Base Task Group. The original network model and language
                were presented in the CODASYL Data Base Task Group's 1971
                report; this is sometimes called the DBTG model.
DC		Data Collection.
DC		Data Communication.
DC		Data Control.
DC		Device Control.
DC		Direct Current.
DCA		Digital Communications Associates.
DCA             Document Content Architecture. DCA defines the rules for
                specifying the form and meaning of a text document.
DCAF		Distributed Console Access Facility.
DCAM		Direct Chip Attach Module.
DCB             Data Control Block.
DCB		Disk Coprocessor Board.
DCC		Digital Command Control.
DCC		Digital Compact Cassette.
DCC		Direct Client Connection.
DCC             Display Combination Code.  A number which indicates both the
                type of display adapter board and the type of monitor
                attached to the video board.
DCD		Data Carrier Detect.
DCE             Data Communication (or Circuit-Terminating) Equipment. The 
                name given to the equipment provided by the network authority 
                (provider) for the attachment of user devices to the network. 
                It takes on different forms for different network types.
DCE             Distributed Computing Environment.
DCE		Distributed Computing Equipment.
DCF		Data Communication Facility.
DCF		Data Compression Facility.
DCF		Data Count Field.
DCF		Driver Configuration File.
DCI             Display Control Interface.
DCL		DeCLaration
DCL		Dec Command Language.
DCL		Device CLear.
DCL		Digital Control Logic.
DCL		Digital Command Language.
DCLGEN          DeCLaration GENerators.
DCS		Data Collection System.
DCS		Data Control System.
DCS		Desktop Color Separation.
.DCT		DiCTionary. File name extension.
DCT             Discrete Consine Transform.
DD              Data Dictionary.
DD		Digital Display.
DD		Double Density.
DDA		Domain-Defined Attribute.
DDB             Deductive DataBase. The emphasis in DDBs has been on deriving
                new knowledge from existing data by supplying the real-world
                relationships in the form of rules.
DDB		Device Dependent Bitmap.
DDBMS           Distributed DataBase Management System. A DDBMS can have the
                actual database and DBMS software distributed over many
                sites, connected by a computer network.
DDC		Digital Data Channel.
DDC1		Display Data Channel One.
DDCE            Digital Data Conversion Equipment.
DDCMP           Digital Data Communications Message Protocol.
DDCS		Distributed Database Connection Services.
DDD             Direct Distance Dialing.
DDDP            Distributed Data Driven Processor. The DDDP from OKI Electric
                has a centralized tag manager and performs token matching
                using a hardware hashing mechanism similar to that of the MDM.
DDE             Data Dictionary Entry. Used in Structure Analysis / Structure
                Design (SA/SD or SASD) portion of the software development
                life-cycle (software engineering).  The data dictionary keeps
                track of all terms / symbols / names used within a given
                model/system/project.  (DD = Data Dictionary)
DDE		Direct Data Entry.
DDE             Dynamic Data Exchange. Method of inter-process communication
                within the Microsoft Windows graphical DOS interface.
DDEML		Dynamic Data Exchange Manager Library.
DDF		Display Data Channel.
DDF		Dynamic Data Formatting.
DDI             Device Driver Interface.
DDI             Direct Dial Inwards.
DDK		Device Driver Kit.
DDL             Data Definition Language. In many DBMSs where no strict
                separation of levels is maintained, one language, called the
                DDL, is used by the DBA and by database designers to define
                the conceptual and the internal schemas.
DDL		Data Description Language.
DDM		Distributed Data Management.
DDM1            Data-Driven Machine #1. The DDM1 was completed at Burroughs
                in 1976, making it the oldest working dataflow machine. It
                uses the static dataflow approach and has its processing
                elements arranged as a tree.
DDN             Defence Data Network.
DDP             Distributed Data Processing. An organization of data
                processing where both processing and data may be distributed
                over a number of different machines in one or more locations.
DDPA            Data Driven Processor Array. The DDPA from Nippon Telephone
                and Telegraph is some six year newer than the DDM1 and is a
                dynamic tagged-token design intended for large scientific
                calculations. The PEs are arranged on a two-dimensional grid
                and are connected to eight other PEs (nearest and next-nearest
                neighbors.
DDR             Digital Data Receiver.
DDS             Digital Data Storage.
DDS		Digital Dataphone Service.
DDS		Design Data Sheet.
DDS		Digital Data Storage.
DDS		Distributed Database Services.
DDT             Digital Data Transmitter.
DEC		DECrement.
DEC		DEvice Clear.
DEC		Digital Equipment Corporation.
DEC DNA         See DNA.
DEC PDP-10      See PDP-10.
DEC PDP-11      See PDP-11.
DEC PDP-8       See PDP-8.
DEC VAX         See VAX.
DEDB            Data Entry DataBase. A DEDB is a special form of HDAM
                database designed for better availability and performance. It
                is a restricted form of hierarchy with only two levels, and
                it may be partitioned into up to 240 areas.
DEDSED          Double-Error Detection Single-Error Correction memory. A
                storage system that uses parity bits to correct single errors
                (i.e. a 02 bit has erroneously become a 12 bit or vica versa)
                and can detect (but not correct) double errors (two errors in
                one word).
DEF		Desktop Functional Equivalent.
.DEF      	DEFinitions. File name extension.
.DEF		DEFaults. File name extension.
DEFRAG		DEFRAGment.
DEK		Data Encryption Key.
DEL             DELete character.
DELSTR		DELete STRing.
DELTA           DEscription Language for TAxonomy.
.DEM		Demonstration. File name extension.
DEMUX           Demultiplexor. A device that has one input and many outputs
                and sends the input to exactly one of the outputs as
                specified by an external control.
DEN             Document Enabled Networking.
DES             Data Encryption Standard.
DES		Date Entry Sheet.
.DES		DEScription File name extension.
DET		Device Execute Trigger.
DEV		DEVice.
DF		Data Field.
DF		Destination Field.
DF		Device Flag.
DF              Direction Flag. A status bit in the 8088 microprocessor.
DF		Double Flag.
DFC		Data Flow Control.
DFD             Data Flow Diagram. This is a diagrammatic method for
                organizing and presenting information-processing requirements.
DFG             Diode Function Generator.
DFM             DataFlow Machine.
DFM		Design For Manufacturability.
DFS		Distributed File System.
DFSMS           Data Facility Storage Management Subsystem.
DFT		Design For Testability.
DFT		Diagnostic Funtion Test.
DFT		Discrete Fourier Transform.
DFT		Distributed Function Terminal.
DFU		Data File Utility.
DFWMAC		Distributed Foundation Wireless Media Access Control.
DGIS            Direct Graphics Interface Standard.
DHCP            Dynamic Host Configuration Protocol.
DHL             Dynamic Head Loading.
.DHP		Dr. Halo Picture. File name extension.
DI		Data In.
DI              Destination Index Register. A value maintained by the 8088
                microprocessor.
DIA             Document Interchange Architecture.
DIB             Device-Independent Bitmap.
DIB		Directory Information Base.
DIBOL		Dec Inc. Business Oriented Language.
.DIC		DICtionary. File name extension.
DID		Direct Inward Dialing.
DIF		Data Interchange Format.
DIFFSENS	DIFFerential SENSe.
DIIP		Direct Interrupt Identification Port.
DIMM            Dual In-line Memory Modules.
DIN		Deutsche Industrie Norm. German equivalent of EIA.
DIO		Data Input-Output.
DIP		Dialup Internet Protocol.
DIP		Digital Imaging Processing.
DIP             Document Insert Protocol.
DIP             Dual In-line Package. A package technology for integrated
                circuits where the pins are aligned in two parallel rows.
DIP		Dual In-line Pin.
DIR		DIRectory.
DIS		Dynamic Impedance Stabilization.
DISA		Data Interchange Standards Association.
DISP		DISPlacement. Offset.
DIT		Directory Information Tree.
DIV		DIVide.
DIVE		Direct Interface Video Extension.
DIW		D-Inside Wire.
.DIZ		Description In Zip. File name extension.
DKNF            Domain/Key Normal Form. The idea behind DKNF is to specify,
                (theoretically, at least) the "ultimate normal form" that
                takes into account all possible types od dependencies and
                constraints.
DL		DownLoad. Also D/L.
DL/1            Data Language One. DL/1 includes the DML of IMS as well as 
                the DDL.
DLC             Data Link Control. DLC governs the synchronization between
                two communicating stations.
DLD		Display List Driver.
DLE             Data Link Escape (character).
DLS             Data Link Switching.
DLT             Digital Linear Tape.
DLL             Dynamic Link Library. A collection of subroutines which are
                linked with a program at the time it is loaded into memory
                rather than permanently placed in the executable.   
                This has the advantage of allowing a single copy of the
                subroutine library to reside on disk or in memory even when
                it is used by many programs.  It also permits all programs
                using the DLL to be updated without recompiling simply by
                installing a new version of the library.
DLM		Dynamic Link Module.
DLR		DOS LAN Requester.
DLT		Digital Linear Tape.
DM		Distributed Memory.
DMA             Direct Memory Access. A type of I/O in which a special DMA 
                controller, rather than the CPU, transfers data between main
                memory and the I/O devices.
DMA             Document Management Alliance.
DMAC		Direct Memory Access Controller.
DMCL            Device Media Control Language. The DMCL allows a 
                specification of the physical storage parameters that govern 
                the mapping of the instances of data into storage for given
                schema description. 
DMD		Digital Micromirror Device.
DME		Distributed Management Environment.
DMF		Distribution Media Format.
DMI             Desktop Management Interface.
DML             Data Manipulation Language. 
DMM		Digital MultiMeter.
DMMS		Dynamic Memory Management System.
DMOS		Double-diffused Metal-Oxide Semiconductor.
DMP             Diagnostic and Monitoting Protocol.
DMP		Dot Matrix Printer.
DMPC		Distributed Memory Parallel Computer.
DMQS      	Display Mode Query and Set.
DMS		Data Management Software. 
DMS		Data Management System.
DMS             Document Management Systems.
DMSD		Digital MultiStandard Decoding.
DMTF            Desktop Management Task Force. A group of companies formed to 
                help standardize and simplify PC network management.
DMY		Day Month Year.
DN		DowN.
DNA             Distributed Network Architecture. DEC has developed DNA as a
                response to the need for an integrated approach to networking
                that includes both WANs and LANs. The DNA is the framework
                for all DEC's communications products.
DNC		Direct Numerical Control.
DNE             Data Link Escape.
DNIC		Data Network Identification Code.
DNIS		Dialed Number Identification Service.
DDNS            Domain Name Server.
DNS             Domain Name System. The application protocol used in the 
                TCP/IP suite to map the symbolic names used by humans into 
                the equivalent fully-qualified network address.
DO		Data Out.
DO		Distributed Objects.
DOC             Department Of Communications. The Canadian DOC label
                indentifies certified equipment. This certification means 
                that the equipment meets certain telecommunications network
                protective, operational, and safety requirements.
.DOC      	DOCument.
.DOC		Documentation. File name extensions.
DOE		Distributed Objects Everywhere.
DO-IT		Disabilities, Opportunities, Internetworking and Technology.
DOMF		Distributed Object Management Facility.
DOS             Disk Operating System. See MS DOS.
DOSEM		Disk Operating System EMulation.
DOS/VSE         Disk Operating System/Virtual Storage Extended.
DOW		Day Of Week.
DP		Data Processing.
DPA		Demand Protocol Architecture.
DPAM		Demand Priority Access Method.
DPAREN		Data PARity ENable.
DPB             Drive Parameter Block. The DOS Drive Parameter Block stores 
                the description of the media layout for a logical drive, as 
                well as some housekeeping information.
DPC		Direct Program Control.
DPCM            Differential Pulse Code Modulation.
DPI		Dots Per Inch.
DPL		Descriptor Privilege Level.
DPL             DOS Parameter List. The DOS Parameter List is used to pass
                arguments to SHARE and network functions.
DPLL            Digital Phase-Locked Loop.
DPM		Digital Panel Meter.
DPM             Dynamic Power Management
DPMA		Data Processing Management Association.
DPMI            DOS Protected-Mode Interface. An API which provides basic
                services for protected-mode programs to allocate memory,
                invoke real-mode software, etc.  See also VCPI.
DPMS		Display Power Management Support.
DPO		Data Phase Optimization.
DPS		Document Processing System.
DPSK            Differential Phase Shift Keying.
DPS PAR         Digital Processing Systems Personal Animation Recorder.
DPtoTP		Display Coordinates TO Tablet Coordinates converting.
DQDB            Distributed Queue Double Bus. DQDB is an other name for QPSX.
                An optical fibre-based network that can be used as a 
                high-speed LAN or MAN that is compatible with the evolving 
                broadband ISDN networks. It operates in a broadcast mode by 
                using two buses each of which transmits small fixed-sized 
                frames - known as cells - in opposite directions. Each bus 
                can operate at hundreds of megabits per second.
DQL		DataEase Query Language.
DR		Data Received.
D/R		Direct or Reverse.
DR              Dynamic Recompilation.
DRAM            Dynamic Random Access Memory. RAM memory which essentially
                consists of a tiny capacitor for each bit of memory.  Since
                capacitors do not hold a charge indefinitely, DRAM must be
                constantly refreshed to avoid losing its contents.  Also, the
                process of reading the contents of the memory are
                destructive, meaning extra time must be spent restoring the
                contents of memory addresses which are accessed, so DRAM is
                slower than SRAM.  See also SRAM.
DRAW		Direct Read After Write.
DR.BOND		Dial-up Router Bandwith ON Demand.
DRDA            Distributed Relational Database Architecture.
DR-DOS		Digital Research-Disk Operating System.
DRDW		Direct Read During Write.
DRI		Digital Research Incorporated.
DRO		Data Request Output.
DRO		Destructive Read-Out.
DRQi            DMA request line i.
DRS		Document Registration System.
.DRS		Driver ReSource. File name extension.
DRV		DRiVe.
.DRV		device DRiVer. File name extension.
.DRW		DRaW. File name extension.
.DRW		DRaWing. File name extension.
DS              Data Segment register. A segment register in the 8088
                microprocessor that holds the base address of the data
                segment.
DS		Data Send.
DS		Data Server.
DS              Decode and Select.
D/S		Dhrystone Per Second.
DS              Directory Service. A protocol entity forming part of the 
                application layer in an OSI suite that is concerned with the 
                translation of symbolic names (or titles), as used by 
                application processes, into fully qualified network 
                addresses, as used within the open systems interconnection 
                environment. Also known as X.500.
DS		Double Sided.
DSA		Digital Signature Algorithm.
DSA		Directory System Agent.
DSAP		Destination Service Access Point.
DSB             Diagnostic Status Byte.
DSC             Document Structure Conventions.
DS-DD		Double Sided, Double Density.
DSE		Data Storage Equipment.
DSE             Data Switching Exchange.
DSEA		Display Station Emulation Adapter.
DSECT           Dummy SECTion.
DSG             Data Set Groups. A HISAM, HDAM or HIDAM database can be
                partitioned into groups of segment types. One primary data
                set group and nine secondary data set groups can be created.
                The primary DSG contains the root segment. Each secondary
                DSG is a separate database containing all segment occurance
                for the type of segments that belong to it.
DS-HD		Double Sided, High Density.
DSIS		Distributed Support Information Standard.
DSL             DataSet Label.
DSM             Distributed System Management.
DSMA		Digital Sense Multiple Access.
DSOC            Decode and Select/Operand fetch Cycle.
DSOM		Distributed System Object Model.
DSP             Digital Signal Processor.
DSP             Domain Specific Part.
DSPU            DownStream Physical Unit.
DS-QD		Double Sided, Quad Density.
DSR             Data Set Ready. A control signal send by, e.g. a modem to a
                universal asynchronous receiver-transmitter (UART) that tells
                the UART the modem is ready to send data.
DSR		Device Status Register.
DSR		Device Status Report.
DSS             Decision Support Systems.
DSS		Digital Signature Standard.
DSS             Dynamic Support System.
DSSS		Direct-Sequence Spread Spectrum.
DSTN		Double Supertwisted Nematic.
DSU             Data Service Unit.
DSVD		Digital Simultaneous Voice and Data.
DSW		Data Status Word.
DSW		Device Status Word.
DT              DynaText.
.DTA		DaTA. File name extension.
DTA             Disk Transfer Address. The Disk Transfer Address indicates
                where functions which do not take an explicit data address
                will read or store data.  Although the name implies that only
                disk accesses use this address, other functions use it as 
                well.
DTD             Document Type Definition. This is a specific markup language,
                written using SGML.
DTE             Data Terminal (or Terminating) Equipment. A generic name for 
                any user device connected to a data network. It thus includes 
                such devices as visual display units, computers and office 
                workstations.
DTE		Dumb Terminal Emulator.
DTI             Department of Trade and Industry.
DTL		Diode-Transistor Logic.
DTMF		Data Tone Multiple Frequency.
DTMF		Dual Tone Multi Frequency.
DTP             Datagram Transport Protocol.
DTP		DeskTop Publishing.
DTP		Distributed Transaction Process.
DTR             Data Terminal Ready. A control signal send by a universal 
                asynchronous receiver-transmitter (UART)to, e.g. a modem
                that tells the modem the UART is ready to receive data.
DTR		Data Transfer Rate.
DTV		DeskTop Video.
DTVC		DeskTop Video Conferencing.
DU		Disk Usage.
DUA		Directory User Agent.
DUAT		Direct User Access Terminal.
.DV		DesqView script. File name extension.
DVC             Desktop Video Conferencing.
DVE		Digital Video Effect.
DVI		Digital Video Interactive.
.DVI		DeVice Independent. File name extension.
DVMRP		Distance Vector Multicast Routing Protocol.
.DVR		device DriVeR. File name extension.
.DWG		DraWinG. File name extension.
DWORD           Doubleword; four bytes.  Commonly used to hold a 32-bit 
                segment:offset or selector:offset address.
DX              Data Register of the 8088 microprocessor.
.DXB		Drawing eXchange Binary. File name extension.
DXC		Data eXchange Control.
DXF		Document eXchange Format.
DXT             Data EXtract. DXT is a utility program that extracts data 
                from IMS databases or VSAM or SAM files and converts it into 
                a sequential file.
