| dfi | TI bqEASY Data Flash Image |
| dfp | Data Flask Package |
| dfq | qs-STAT Q-DAS Shared Data File |
| dfq | SmartWare Query Definition File |
| dfr | DataFlex Registration Data |
| dfr | SmartWare Report Definition File |
| dfs | BrainSuite Surface |
| dfs | SmartWare Sort Definition File |
| dfs2 | MIKE 11 Results Data |
| dft | SmartWare Transact Definition File |
| dft | EES Default Information |
| dfv | Microsoft Word Print Format Template |
| dfw | SmartWare Cross-Tab Definition File |
| dfw | Derive for Windows Data |
| dfx | SmartWare Relate Definition File |
| dfx | qs-STAT Q-DAS Value File |
| dfxml | Digital Forensics XML |
| dg-key | DigiGuide Key Data |
| dgb | Digitarch FlashCAD Drawing Database |
| dgdb | Data Guardian Database |
| dgf | DUNE Grid Format File |
| dgi | HDConvertToX Input |
| dgimglib | DigiGuide Image Library |
| dgl | DigiGuide Language Data |
| dgmarker | DigiGuide Marker Data |
| dgnlib | Bentley MicroStation Design Library |
| dgo | Dell EqualLogic Diagnostic Log |
| dgp | Creator Generated Waveform |
| dgprint | DigiGuide Print Template |
| dgscheme | DigiGuide TV Scheme Data |
| dgscript | DigiGuide Script |
| dgtoolbar | DigiGuide Toolbar Data |
| dgz | Dega GZipped Saved State Data |
| dhg | Direct Hit Graphics Engine Output |
| dhl | Deepnet HTTP Server Log |