| Alpha Five Storage Format | |
| Alpha Software | |
| Ads |
File with an .ASI extension contains data related to variables used within a project of a network application.
ASI files are utilised as parts of projects created within the Alpha Five (Alpha Anywhere since the year 2013), which is a software used to design network application.
Windows
| .a | Unix Static Object Code Library Format |
| .a2w | Alice Program World Format |
| .actx | DS Game Maker Action Description Format |
| .ada | ADA Language Source Code Format |
| .addin | Microsoft Visual Studio Addin Format |
| .ads | Ada Package Specification |
| .agi | Asterisk Gateway Interface Format |
| .alb | Alpha Five Data Dictionary |