| 3pi | 3rd PlanIt Data |
| 3tf | Crystal Reports Chart Template |
| 3w | XYZware 3D Document |
| 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 |
| abs | Abs Spreadsheet |
| abt | ED-IT PC AsIs Braille Text File |
| abw | AbiWord Document |
| 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 |