| avz | AviSys v6 Database Backup |
| aw | Answer Wizard Index |
| aw5 | MESA Actigraphy Actigraph Database |
| awd | AWARD BIOS Firmware Update |
| awe | Adobe Acrobat Bookmark XML Data |
| awh | ActiveWorlds Browser Help Data |
| awkw | Awkwords Generated Data |
| awn | Avant Window Navigator Theme Data |
| awr | Ad-Aware Reference Data |
| awr | Iconics AlarmWorX32 Report File |
| awsec | AirWatch Inbox Secure Content |
| awses | Active WebCam Session Data |
| awv | Iconics AlarmWorX32 Viewer File |
| awzip | ActiveWords Compressed Solution Data |
| axdt | ANSYS External Data |
| axe | Autoroute Export Data |
| axis | Microsoft SSAS AXIS Data |
| axm | AXMEDIS Object |
| axq | EditRocket Ada Editor Data |
| axs | AXIS Data File |
| axt | Adobe Photoshop Replace Color Setup |
| axtr | Microsoft Dynamics AX Task Recording Package |
| axw | Analyzer StateForms Data |
| ayt | Ayat Data |
| ayu | AY Paste Data |
| ayy | FSUTMS Binary Transit Plotting Model |
| az! | Vuze Partial Download |
| azf | AirZip FileSECURE AZF File |
| azk | DMDX Output Document |
| azm | BTS Master AZM Map Data |
| azs | AirZip FileSECURE AZS File |
| azt | AutoZilla Template File |
| azz | AZZ Cardfile Database |
| b1 | VTrain Data File |
| b1j | BookJones Data |