| article | Twixl Publisher Article |
| arx | Artista Cross Stitch Embroidery Data |
| as5 | CivilCAD v5 ASCII Document |
| asc | ASCII Armored GPG/PGP File |
| Plain Text Document |
| ascii | Plain Text Document |
| asd | Alphacam Stone Drawing |
| Astound Media Data |
| Astound Presentation |
| Microsoft Word AutoRecovery File |
| ase | Aseprite Sprite Data |
| Autodesk 3D Studio ASCII Scene Export |
| aseprite | Aseprite Sprite Data |
| asm | Solid Edge Assemblies Document |
| asp | ASAP WebShow Presentation |
| Astound Presentation |
| assbin | Allegorithmic Substance Painter Scene |
| ast | Ability Spreadsheet Template |
| Astound Media Data |
| ClarisWorks Assistant |
| astx | Adobe Story Exported Script |
| asy | Asymptote Document |
| at2 | Aldus Persuasion v2 Template |
| at65 | Adobe PageMaker for Mac 6.5 Template |
| atd | Alphacam Lathe Drawing |
| atl | IR Prognosis Atlas Document |
| atom | Atom Syndication Format File |
| atw | AnyTime Organizer Deluxe Document |
| av | Final Draft AV v1 Document |
| avery | Avery Design and Print Online Label |
| aw | Applixware Words Document |
| awd | Ability Draw Document |
| Microsoft Fax Image |
| awg | Ability Draw Vector Graphic |
| awp | Ability Write Template |
| aws | Ability Spreadsheet Document |
| awss | Microsoft Works for Mac Spreadsheet |
| awt | AbiWord Template |
| aww | Ability Write Document |
| awwp | Microsoft Works for Mac Document |
| ax2 | Apex Sketch v2 Document |
| ax3 | Apex Sketch v3 Document |
| ax4 | Apex Sketch v4 Document |
| ax5 | Apex Sketch v5 Document |
| axls | Authentica Secure Office Protected Excel Document |
| axz | Apex Sketch v6 Document |
| b | IRIS Editor Shortened Format File |
| b4u | docPointer Visual ReadMe Document |
| bak | Canvas Drawing Backup |
| bakx | MakeMusic Finale Notation Backup |
| bamboopaper | Wacom Bamboo Paper Document |
| ban | Broderbund PrintMaster Banner |
| bax | Bluebeam PDF Revu Markup XML |
| bbcd | BobCAD-CAM Document |
| bbdoc | Buildbox Document |
| bbe | Brainbloom Document Exchange File |
| bbl | BibTeX Bibliographic Reference |
| bbs | BBS Directory List |
| bbxt | BBEdit Document |
| bc5 | Impression Document |
| bcc | Calendar Creator v7 Document |
| bcd | Business Card Designer Plus Document |
| OfficePrinter Label Document |
| bcf | Belltech Business Card Designer Pro Document |
| bcn | Business Card Pro Design |
| bco | Business Card Designer Plus Document |
| bcp | Business Card Designer Plus Document |
| bcsv | Binary CSV Data |
| bdb | Microsoft Works Database Backup |
| bdc | West Point Bridge Designer Document |
| bdl | PTC Creo Bundle File |
| bean | Bean Rich Text Document |
| bfc | Windows 95 Briefcase Document |
| bff | WorldToolKit Binary NFF Data |
| bfx | Bluebeam PDF Revu Exchange XML |
| bgcf | Belltech Greeting Card Designer Document |
| bgv | BonanzaGraf Financial Presentation |
| bib | BibTeX Document |
| big5 | Chinese Text Document |
| bimx | ArchiCAD BIMx Document |
