| !ws | WordStar 2000 Temporary File |
| 1 | Unix Manual Page |
| 123 | Lotus 1-2-3 Worksheet |
| 123c | Autodesk 123C Drawing |
| 123d | Autodesk 123D Drawing |
| 123dx | Autodesk 123D Design Model |
| 12m | Lotus 1-2-3 Smartmaster Template |
| 1sp | Microsoft OneNote 2010 Mobile Document |
| 1st | Readme Document |
| 2 | Unix Manual Page |
| 2cd | DoubleCAD Document |
| 2d | Cadwork 2D Drawing |
| VersaCAD 2D Drawing |
| 2dc | Cadwork 2D Drawing |
| 2dl | ArchiCAD 2D Lines Data |
| 3 | Unix Manual Page |
| 3d | CAD-3D Model |
| Cadwork 3D Drawing |
| 3d2 | CAD-3D Model |
| 3da | ArtCAM Pro 3D Assembly Data |
| 3db | 3DMark Report Database |
| 3dc | Cadwork 3D Drawing |
| 3dd | Cadmatic 3DD Model |
| 3df | Informative Graphics 3D Format Document |
| 3dg | 3D Grapher Document |
| 3di | Cadence Allegro 3D Model |
| 3dl | LightConverse 3D Scene |
| 3dm | OpenNURBS 3D Model |
| QuickDraw 3D Metafile |
| 3dmf | QuickDraw 3D Metafile |
| 3dml | Flatland 3DML Document |
| 3ds | Autodesk 3D Studio Scene |
| 3dt | 3D Topicscape Document |
| 3dx | Rhino 3D Model |
| 3dxml | 3D XML Document |
| 3ko | NGRAIN SDK 3D Data |
| 3mf | 3D Manufacturing Format Document |
| 3ml | SimStudio 3D Model |
| 3pi | 3rd PlanIt Data |
| 3tf | Crystal Reports Chart Template |
| 3w | XYZware 3D Document |
| 3wn | XYZware Nobel 3D Model |
| 3ws | XYZware Nobel 3D Model |
| 4 | Unix Manual Page |
| 4dse | 4D Database for Mac Quick Report Document |
| 4dv | 4DIM Interactive Animation |
| 4w6 | 4D Write Document |
| 4w7 | 4D Write Document |
| 4wp | 4D Write Pro Document |
| 4wt | 4D Write Template |
| 5 | Unix Manual Page |
| 6 | Unix Manual Page |
| 602 | Text602 Document |
| 7 | Unix Manual Page |
| 8 | Unix Manual Page |
| 9 | Unix Manual Page |
| a2l | ASAP2 ECU Description |
| a3d | Amapi Designer 3D Model |
| a4d | 4DIM Model Animation |
| aad | Atlantis Word Processor Document Backup |
| aaf | Advanced Authoring Format File |
| abc | Business Card Maker Document |
| Micrografx ABC FlowCharter 6 Document |
| abd | Worksheet Crafter Document |
| abk | Ability Write Document Backup |
| abs | Abs Spreadsheet |
| abt | Braille2000 Annotated Braille Text |
| ED-IT PC AsIs Braille Text File |
| abw | AbiWord Document |
| ac | AC3D Model |
| ac3d | AC3D Model |
| ac5 | ArtCut 5 Document |
| ac6 | ArtCut 6 Document |
| accd | Microsoft Access 2007 Database |
| accdb | Microsoft Access 2007 Database |
| accdc | Microsoft Access 2007 Signed Package |
| accde | Microsoft Access 2007 Executable |
| accdr | Microsoft Access 2007 Run-time |
| accdt | Microsoft Access 2007 Database Template |
| accdw | Microsoft Access 2007 Database Link |
| accfl | Microsoft Access Field Template |
| accft | Microsoft Access 2007 Data Type Template |
| acp | Macromedia Action! Document |
| act | Macromedia Action! Template |
| ad65 | Adobe PageMaker 6.5 for Mac Document |
| adb | Ability Database Document |
| add | Alphacam Diecut Drawing |
| ade | Microsoft Access Project Extension |
| adf | Active-HDL Design Document |
| ARIS Express Document |
| I-DEAS Associated Data |
| adoc | AsciiDoc File |
| Authentica Secure Office Protected Word Document |
| ados | ADOS Compound Document |
| adox | ActivDox Document |
| adsk | Autodesk Exchange File |
| ad_asm | Alibre Design CAD Assembly Document |
| ad_bom | Alibre Design Bills of Material Data |
| ad_drw | Alibre Design 3D CAD Drawing |
| ad_prt | Alibre Design CAD Part Document |
