| wcz | Chameleon Clock Wallpaper |
| wd3 | Offline Explorer Data |
| wda | AutoCAD Electrical Project User Attributes Data |
| wdc | SOBEK Wind Data |
| wdc | WinDaq Waveform Browser Data |
| wdh | WinDaq High Resolution Data |
| wdl | AutoCAD Electrical Project Labels Data |
| wdn | AutoCAD Electrical Project Terminal Numbering Data |
| wdq | WinDaq Acquired Data |
| wdq | Offline Explorer Queue |
| wdr | AutoCAD Electrical Project Ratings Data |
| wdseml | Thunderbird Searchable Email File |
| wdsp | WebDrive Data |
| wdt | AutoCAD Electrical Project Titles Data |
| wdv | TracePlus Web Detective Data |
| wdw | AutoCAD Electrical Project Wires Data |
| wea | Autodesk Ecotect Analysis Weather Data |
| webarchive | Safari Web Archive |
| webbookmark | Safari Web Bookmark Data |
| webhistory | Safari Web History Data |
| webinar | GoToWebinar Session Data |
| weboogl | WebOOGL Data |
| webpart | Microsoft Sharepoint Web Part |
| webtest | Fiddler Saved WebTest Data |
| webx | Akamix Saved Search Data |
| weg | PTV VISSIM Path Data |
| weights | SAM Sequence Weights Data |
| wel | Heliosoft Seismaster Input Well Path |
| wel | MODFLOW Well Package |
| wells | ParFlow Well Output Data |
| wenlin | Wenlin Software Data |
| wes | WE7000 Control Software Setup Data |
| wex | WexView Browser Course Data |
| wf4 | PTC Creo Parametric Symbol Data |
| wff | FRAMES Water Flux File |