D

File extensions starting with the letter D...

  .D    Dialect Source Code File
  .D2D  3D Fassade Plus 2D/3D Object File
  .D3D  CorelDream 3D File
  .D64  Commodore 64 Emulator Disk Image
  .D8A  AmBiz Productivity Pak Catalog
  .DAD  Chromeleon Channel Raw Data
  .DAO  Windows Registry Backup
        IsoBuster File
  .DAP  Omnis5 Application File
        MS Access Data Access Page
  .DAT  Data (multiple programs)
        WordPerfect Merge Data
        (also possibly) MPEG File
        Mitsubishi DJ-1000 and Photorun Native Format
  .DB   Paradox Database
        Progress Database
        Solid Database
  .DB2  dBase II File
  .DBC  MS Visual Foxpro Database Container
  .DBF  Database (multiple programs) [started as dBASE]
        Oracle 8.x Tablespace File
  .DBK  dBase Database Backup
        Orcad Schematic Capture Backup File
  .DBM  Cold Fusion Template
  .DBO  dBase IV Compiled Program File
  .DBQ  Paradox Memo
  .DBT  Database Text File [dBASE]
  .DBV  Flexfile Memo Field File
  .DBW  DataBoss Database File
  .DBX  Database (multiple programs)
        DataBeam Image
        MS Visual Foxpro Table
  .DC   DesignCAD CAD File
  .DC2  DesignCAD CAD File
        Kodak DC25 Digital Camera File
  .DC5  DataCAD Drawing File
  .DCA  Visual Basic Active Designer Cache
        IBM DisplayWrite Document Content Architecture Text File
  .DCB  Concordance Database Control Block
  .DCD  Document Content Description File 
        FORTRAN Data File
        INMOS Transputer Development System Occam Object Code
  .DCF  Design Rule for Camera File Systems File
        DynSite Configuration File
        Dyadic Data File
  .DCM  DCM Module Format
  .DCP  Delphi Compiled Packages
        OS/2 Data CodePage
  .DCR  Shockwave File
  .DCS  Quark Desktop Color Separation Specification
        ACT! Activity Data File
  .DCT  Dictionary (various)
        MS Visual Foxpro Database Container
  .DCU  Delphi Compiled Unit
  .DCX  FAX Image  [Viewer]
        PC-Paintbrush File [SwiftView]
        Bitmap Graphics  [Viewer]  
        Macros
        MS Visual Foxpro Database Container
  .DD   Macintosh Compressed Disk Doubler Archive
  .DDB  Bitmap Graphics File
        INMOS Transputer Development System Occam Debugging Info
  .DDE  Dynamic Data Exchange
  .DDF  BTRIEVE Database
        Bitstream Fontware File
  .DDI  DiskDupe Image
        Disk Doubler Image
  .DDP  OS/2 Device Driver Profile File
  .DDS  INMOS Transputer Development System Occam Compiler Descriptor
  .DEB  DOS Debug Script
        Debian Linux Package
  .DEF  Definitions
        Defaults
        SGML Tag Definition
        SmartWare II Data File
        C++ Definition
        3D Fassade Plus Define Module File
        Geoworks Assembly Header File
  .DEI  Gerber Design Engineered Interface 
  .DEL  Data
  .DEM  Descent Demonstration
        USGS Map  
  .DEP  Setup Wizard Dependency  
  .DER  Certificate File
  .DES  Description Text
  .DEV  Device Driver
        Device Independent TeX
        LaTeX File
  .DEZ  DES Encrypted Zip File
  .DF   Lightscape Parameters
  .DF1  Omnis7 and Omnis Studio Database File (also .DF2, .DF3, etc.)
  .DFD  File Flow Diagram Graphic
  .DFI  Digifont Outline Font Description
  .DFL  Signature Default Program Settings
  .DFM  Delphi Forms
        File Flow Diagram Model  
  .DFS  Delight Sound File
  .DFV  Word Print Format Template
  .DG   Autotrol Graphics
  .DGC  TurboTax-related File
  .DGN  Microstation95 CAD Drawing File
        Intergraph Graphics
  .DGO  Dimitrius Settings File (Dimitrius is program author)
  .DGS  AT Advanced Diagnostics File
  .DH   Geoworks Dependency Information File
  .DHP  Dr. Halo PIC
  .DHT  Gauss Data File
  .DIA  Computer Support Corp Diagraph Graphics File
  .DIB  Device-Independent Bitmap Graphic  [Viewer]
  .DIC  Dictionary (various)
  .DIF  Data Interchange Format
  .DIG  Text Document
        Digilink Format
        Sound Designer Audio File
  .DIP  Graphics File
  .DIR  Procomm Plus Dialing Directory
        Macromedia Director File
        DEC VAX Directory
  .DIS  Ray Tracer File
        DATAIR Data Import Specification Layout File
        VAX Mail Distribution File
        Corel Draw Thesaurus
  .DIT  MS Win2000 Active Directory Schema
  .DIVX  Movie Encoded with DivX-codec
  .DIZ  Description In Zip File
  .DKB  DKBTrace Ray-Traced Graphics File
  .DL   Animations file
  .DLD  Lotus File
  .DLG  Dialog Resource Script
        C++ Dialogue Script
  .DLK  INMOS Transputer Development System Occam Compiler Link Info
  .DLL  Dynamic Link Library
        CorelDraw Export/Import Filter
  .DLM  Dirty Little Helper Cheat File
  .DLS  Downloadable Sounds (Interactive Music Architecture)
        Norton DiskLock Setup File
  .DLU  Dirty Little Helper Update File
  .DMD  Visual dBASE Data Module
  .DMF  Delusion/XTracker Digital Music File
        Packed Amiga Disk Image
  .DML  Darn! Shopping! Mall File
  .DMO  Demo  
  .DMP  Dump (various)
        INMOS Transputer Development System Occam Core Dump
  .DMS  Compressed Archive  
  .DNE  Darn v5+ (Windows) Events List
  .DNS  DynSite Plug-in File
  .DOB  User Document Form File  
  .DOC  Document or Documentation (many programs/formats)
        MS Word Document
        DisplayWrite 4 File
  .DOG  Laughing Dog Screen Saver
  .DOH  Geoworks Dependency Information File

  .DOS  Text File/DOS Specification Info
  .DOT  MS Word Document Template
        Corel Lines-Definition
  .DOX  Text File
        MultiMate Document
        User Document Binary Form File  
  .DOZ  VENDINFO Description Out of Zip File
  .DP   Daily Planner Calendar File
        DataPhile Data File
  .DPA  Serif DrawPlus Animation
  .DPJ  DeskProto CAM Project File
  .DPK  Delphi Package File
  .DPL  Borland Delphi 3 Packed Library
  .DPP  Serif DrawPlus Drawing
  .DPR  Borland C++ (or Delphi) Default Project
  .DPT  Publish-It! Publication File
  .DPX  Digital Moving Picture Exchange
  .DQY  MS Excel ODBC Query File
  .DR9  Directory File
  .DRC  Orcad Schematic Capture Design Rules Check Report File
  .DRES  Diagnosis Results
  .DRN  Darn for DOS
  .DRS  WordPerfect Driver Resource
  .DRV  Device Driver
  .DRW  Drawing (various)
        Micrografx Vector Graphic
        Pro/E Drawing
  .DS4  Micrografx Designer Graphics (ver 4)
  .DSC  Oracle Discard File
        Nikon Coolpix Disk Identification File
  .DSCE  Diagnosis Scenario
  .DSD  DataShaper Database File
        Document Structure Definition File 
  .DSES  Diagnosis Session
  .DSF  Micrografx Designer
        PC-TRUST Document Signer (Extension means file is signed)
        Delusion/XTracker Digital Sample
  .DSG  Doom Saved Game
  .DSK  Borland C++ or Turbo Pascal Project Desktop File
        Novell Driver File
  .DSL  Lingvo User Feature Dictionary
  .DSM  Delphi Symbol File
        Digital Sound Module Tracker Format
        Dynamic Studio Music Module
  .DSN  ODBC Data Source
        SureThing Office Labeler (formerly DesignExpress) Document
        Object System Designer Design
        Orcad Schematic Capture Schematic File
  .DSP  Signature Display Parameters
        Dr. Halo Graphic Screen Driver
        MS Developer Studio Project
  .DSQ  Corel QUERY File
  .DSR  WordPerfect Driver
        Active Designer File  
  .DSS  Digital Soup Digital Sound File
        DCC Active Designer File
        Digital Speech Standard File (Voice Recorders & IBM's ViaVoice)
  .DST  PC-RDist Distribution File 
  .DST  Embroidery Machines Graphics File
  .DSW  MS Developer Studio Workspace
        Borland C++ Desktop Settings
  .DSX  Active Designer Binary File  
  .DT_  Macintosh Data File Fork
  .DTA  Data (Various)
  .DTD  SGML Document Definition File
  .DTEA  Diagnosis Template Archive
  .DTF  Q&A Database  
        MS Exchange Header File (Used when sending to Lotus Notes)
  .DTM  DigiTrekker Module
  .DTP  SecurDesk! Desktop
        Timeworks Publisher Text Document
        Pressworks Template File
  .DUN  Dial-Up Network
  .DUP  Duplicate Backup
  .DV   DESQview Script
        Digital Video File
  .DVC  Lotus File
  .DVF  DV Studio Camcorder Graphics File
  .DVI  Device Independent Document  
  .DVP  DESQview Program Information
        AutoCAD Device Parameter
  .DVR  Device Driver
  .DW2  DesignCAD Drawing File
  .DWC  Compressed Archive
  .DWD  DiamondWare Digitized File
  .DWF  Autodesk WHIP! Drawing Web File
        MS WHIP autoCAD REader Drawing Web File
  .DWG  AutoCAD Drawing Database
  .DWP  Dweep Game Levels
        DeScribe Document File
  .DWS  Dyadic Workspace File
  .DWT  AutoCAD Template/Prototype File
        Macromedia Dreamweaver Template File
  .DX   Document Imaging File
        Digital Electric Corporation (DEC) Data Exchange File
  .DXB  Drawing Interchange Binary
  .DXF  AutoCAD Drawing Interchange Format
  .DXN  Fujitsu dexNet Fax Document
  .DXR  Macromedia Director Protected Movie File
  .DYN  Lotus File