| Abbreviation | Definition |
|---|---|
| ASMT | Administrative Systems Management Team |
| ASN | Abstract Syntax Notation |
| ASO | Application Service Object |
| ASP | Active Screen Protocol |
| ASP | Advanced Spatial Parameterization |
| ASP | Advanced Systems Protocol |
| ASR | Apple Software Restore |
| ASR | Automated System Recovery |
| ASRS | Automatic Storage and Retrieval System |
| AST | Abstract Syntax Tree |
| ASTS | Asynchronous System Traps |
| ASU | Apple Software Updates |
| AT | Advanced Technology |
| ATA | Advanced Technology Architecture |
| ATA | Advanced Technology Attachment |
| ATAM | Architecture Tradeoff Analysis Method |
| ATAPI | Advanced Technology Attachment Packet Interface |
| ATC | Abstract Test Case |
| ATC | Advanced Transfer Cache |
| ATCA | ADVANCED Telecommunications COMPUTING ARCHITECTURE |