| # File Extensions |
File types with extensions that start with a number or symbol.
| Extension | File Type | File Summary |
| .!bt | Misc | BitTorrent Incomplete Download File |
| .!ut | Misc | uTorrent Incomplete Download |
| .$$$ | Backup | Temporary File |
| .$01 | Manufacturer | DOS Pipe File |
| .$db | Backup | dBASE Temporary File |
| .$er | Database | GroupWise Database |
| .0 | Compressed | Hacha Split Archive File |
| .0 | Game | M3 DS Real Save File |
| .0 | System | Shared Library Link File |
| .000 | Compressed | DoubleSpace Compressed File |
| .000 | Misc | Windows CE Installation Data File |
| .000 | Disk Image | Virtual CD ISO File |
| .001 | Misc | SplitJoin Split File |
| .001 | Manufacturer | Multimedia Fusion Backup File |
| .001 | Misc | 001 File Manager Split File |
| .001 | Game | Snes9x Slot 2 Saved State |
| .001 | Misc | 001 File Joiner & Splitter File |
| .001 | Backup | HJSplit Split Archive |
| .001 | Raster Image | Fax File |
| .001 | Backup | Norton Ghost Disk Backup |
| .0xe | Executable | F-Secure Renamed Virus File |
| .1 | Misc | Unix Section 1 Man Page |
| .113 | Backup | Iomega Backup File |
| .123 | Spreadsheet | Lotus 1-2-3 Spreadsheet |
| .123 | CAD | PCB123 Circuit Board Design |
| .1pe | Data | TurboTax Form File |
| .1ph | Data | TurboTax File |
| .1st | Text | Readme File |
| .256 | Settings | Descent 2 Color Palette File |
| .264 | Video | Ripped Video Data File |
| .2bp | Raster Image | Pocket PC Bitmap Image File |
| .2d | CAD | VersaCAD 2D Drawing File |
| .2mg | Disk Image | Apple IIGS Disk Image |
| .360 | Raster Image | 360desktop Panorama File |
| .386 | System | Windows Virtual Device Driver |
| .3d | 3D Image | Stereo CAD-3D Image File |
| .3d2 | 3D Image | Stereo CAD-3D 2.0 Image File |
| .3d4 | 3D Image | Stereo CAD-3D 2.0 Image File |
| .3da | 3D Image | 3D Assembly File |
| .3dd | GIS | ArcGlobe Document |
| .3df | 3D Image | 3D Format |
| .3dl | 3D Image | LightConverse 3D Model File |
| .3dm | 3D Image | Rhino 3D Model |
| .3dmf | 3D Image | QuickDraw 3D Metafile |
| .3don | 3D Image | Scrutinize 3D Mesh File |
| .3dr | Data | 3DMark Results File |
| .3ds | 3D Image | 3D Studio Scene |
| .3dt | Data | 3D Topicscape File |
| .3dv | 3D Image | 3D VRML World |
| .3dx | 3D Image | Rhino 3D Model File |
| .3dxml | 3D Image | Dassault Systemes 3D XML File |
| .3g2 | Video | 3GPP2 Multimedia File |
| .3gp | Video | 3GPP Multimedia File |
| .3gp2 | Video | 3GPP Multimedia File |
| .3gpp | Video | 3GPP Media File |
| .3gpp2 | Video | 3GPP2 Multimedia File |
| .3me | Data | TurboTax Form File |
| .3mm | Video | 3D Movie Maker Movie Project |
| .3p2 | Video | 3GPP Multimedia File |
| .3pe | Data | TurboTax 2008 Form File |
| .411 | Raster Image | Mavica Thumbnail Image |
| .4db | Manufacturer | 4th Dimension Database Structure File |
| .4dd | Database | 4th Dimension Database Data File |
| .4dl | Database | 4th Dimension Database Log File |
| .4dv | Data | 4D View Ultrasound File |
| .4mp | Audio | 4-MP3 Database File |
| .4ui | Page Layout | ForeUI Plot File |
| .555 | Game | Black & White Weather Settings File |
| .60d | Video | CCTV Video Clip |
| .669 | Audio | UNIS Composer 669 Module |
| .6cm | Audio | Six Channel Module |
| .787 | Video | AVTECH CCTV Video File |
| .7z | Compressed | 7-Zip Compressed File |
| .83p | Misc | TI-83 Calculator File |
| .8ba | Plugin | Photoshop Plug-in |
| .8bc | Plugin | Photoshop 5.0 Plug-in |
| .8be | Plugin | PhotoDeluxe Plug-in |
| .8bf | Plugin | Filter Factory Image Filter |
| .8bf | Plugin | Photoshop Filter Plug-in |
| .8bi | Plugin | Photoshop Plug-in |
| .8bi8 | Plugin | Photoshop Plug-in |
| .8bl | Plugin | Photoshop Plug-in |
| .8bs | Plugin | Photoshop 5.0 Selection Plug-in |
| .8bx | Plugin | PhotoDeluxe Plug-in |
| .8by | Plugin | PhotoDeluxe Plug-in |
| .8cm | Audio | Eight Channel Module |
| .8li | Plugin | Photoshop Scripting Plug-in |
| .8med | Audio | Amiga OctaMed Music File |
| .8pbs | Raster Image | Adobe Photoshop Macintosh File |
| .8st | Settings | 8start Launcher File |
| .8svx | Audio | Amiga 8-Bit Sound File |
| .8xg | Data | TI-83/84 Plus Group File |
| .8xi | Raster Image | TI-83/84 Plus Picture File |
| .8xk | Data | TI-83 Plus Application Upgrade File |
| .8xp | Misc | TI-83 Plus Calculator File |
| .8xs | Data | TI-83/84 Plus String File |
| .8xu | System | TI-83 Plus Operating System File |
| .8xv | Data | TI-83/84 Plus Variable File |
| .^^^ | Database | Pervasive.SQL Database File |
| .__a | Backup | File Splitter & Joiner Encrypted File |
| .__b | Backup | File Splitter & Joiner Encrypted Archive File |
| .{pb | Data | Corel WordPerfect Document Index File |
| .~hm | Data | HostMonitor TestList Backup File |