| DMD | Corel Data Modeling Desktop | 
| DMD | Visual dBASE Data Module | 
| DMF | Delusion/XTracker Digital Music File | 
| DMF | Packed Amiga Disk Image | 
| DMO           | Duke Nukem, Redneck Rampage Saved Game | 
| DMP | Dump (various) | 
| DMS | Packrat Database Index | 
| DMS | Compressed Archive | 
| DNE | Darn v5+ (Windows) Events List | 
| DNE | Netica Bayes Net Text File (More info) | 
| DOB | User Document Form File | 
| DOC | Document or Documentation (various) | 
| DOC | MS Word Document | 
| DOG | Laughing Dog Screen Saver | 
| DOH | Geoworks Dependency Information File | 
| DOS | Text File/DOS Specification Info | 
| DOT | Microsoft Word Document Template | 
| DOT | Corel Draw Line Description | 
| DOX | MultiMate Word Processor Document | 
| DOX | Microsoft ActiveX Binary Form | 
| DOX | Text File | 
| DOZ | VENDINFO Description Out of Zip File | 
| DP | DataPhile Data File | 
| DP | Daily Planner Calendar File | 
| DPA | Serif DrawPlus Animation | 
| DPG | Windows Applications Manager Deleted Program Group | 
| DPI | Pointline Image | 
| 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 | 
| DRC | Orcad Schematic Capture Design Rules Check Report File | 
| DRN | Darn for DOS | 
| DRS | Corel Draw Perfect Font | 
| DRS | WordPerfect Driver Resource | 
| DRS | Age of Empires 2 Archive | 
| DRV | Device Driver | 
| DRW | Micrografx Vector Graphic | 
| DRW | Drawing (various) | 
| DRX | Adobe Photoshop Tutorial | 
| DS | TWAIN Data source file | 
| DS4 | Micrografx Designer Graphics (ver 4) | 
| DSC | Oracle Discard File | 
| DSC | Nikon Coolpix Disk Identification File | 
| DSD | DataShaper Database File | 
| DSD | Document Structure Definition File  | 
| DSF | Micrografx Designer v7.x | 
| DSF | Delusion/XTracker Digital Sample | 
| DSG | Doom Saved Game | 
| DSK | Archive for Lotus Smart Suite Setup | 
| DSK | Borland C++ or Turbo Pascal Project Desktop File | 
| DSK | Novell Driver File | 
| DSL | Lingvo User Feature Dictionary | 
| DSM | Dynamic Studio Music Module | 
| DSM | Delphi Symbol File | 
| DSM | Digital Sound Module Tracker Format | 
| DSN | ODBC Data Source | 
| DSN | SureThing Office Labeler Document | 
| DSN | Orcad Schematic Capture Schematic File | 
| DSP | Microsoft Developer Studio Project | 
| DSP | Dr. Halo Graphic Screen Driver | 
| DSP | Signature Display Parameters | 
| DSQ | Corel QUERY File | 
| DSR | Active Designer File | 
| DSR | WordPerfect Driver | 
| DSS | Digital Soup Digital Sound File | 
| DSS | Digital Speech Standard File | 
| DST | Micrografx Designer Template | 
| DST | Embroidery Machines Graphics File | 
| DSW | Microsoft Developer Studio Workspace | 
| DSW | Borland C++ Desktop Settings | 
| DSX | Active Designer Binary File | 
| DT_ | Macintosh Data File Fork | 
| DTA | Data (various) | 
| DTD | SGML Document Type Definition File | 
| DTF | Symantec Q&A Relational Database Data File | 
| DTM | DigiTrakker Module | 
| DTP | Pressworks Template File | 
| DTP | Timeworks Publisher Text Document | 
| DTP | SecurDesk! Desktop | 
| DTP | Datastorm Technologies, Inc. ProComm Program Patch | 
| DUN | Dial-Up Network | 
| DUP | Duplicate Backup | 
| DV | Digital Video File | 
| DV | DESQview Script | 
| DVB | Visual Basic for Applications Macro Project | 
| DVC | Lotus File | 
| DVF | DV Studio Camcorder Graphics File | 
| DVI | TeX Device Independent Document | 
| DVM | Movie File | 
| DVP | DESQview Program Information | 
| DVP | AutoCAD Device Parameter | 
| DVR | Device Driver | 
| DW2 | DesignCAD Drawing File | 
| DWC | Compressed Archive | 
| DWD | DiamondWare Digitized File | 
| DWF | Autodesk Vector Graphic | 
| DWG | AutoCAD Drawing Database | 
| DWG | Drafix CAD Drawing | 
| DWP | Dweep Game Levels | 
| DWP | DeScribe Document File | 
| DWS | Dyadic Workspace File | 
| DWS | AutoCAD Standardisation File | 
| DWT | AutoCAD Template/Prototype File | 
| DWT | Dreamweaver Template File | 
| DX | MultiMate Word Processor Document | 
| DX | Digital Electric Corporation (DEC) Data Exchange File | 
| DX | Document Imaging File | 
| DX | Autotrol Document Image | 
| DXB | AutoCAD Database | 
| DXB | Drawing Interchange Binary | 
| DXF | AutoCAD Drawing Interchange File Format | 
| DXF | Data Exchange File | 
| DXN | Fujitsu dexNET Fax Document | 
| DXR | Macromedia Director Protected Movie File | 
| DYN | Lotus File |