| CARAM | Content-Addressable Random Access Memory |
| WCMS | Web Content Management System |
| CMS | Content Management System |
| CSS | Content Scrambling System |
| CSS | Content Scrambling System Schutzverfahren gegen das unlizenzierte Abspielen von DVDs |
| CBIRS | Content Based Image Retrieval System |
| TACAS | Terminal Access Controller Access System |
| ADMA | Advanced Direct Memory Access [engl.] |
| ATDMA | Advanced/Asynchronous Time Division Multiple Access [engl.] RACE Forschungsvorhaben |
| AOS | Advanced Operating System |
| ASB | Advanced System Bus [engl.] |
| ASB | Advanced System Buffering [engl.] |
| AFS | Advanced File System [engl.] |
| APS | Advanced Photo System [engl.] Kleinbildfotosystem mit magnetischer Aufzeichnung |
| FACS | Fibronics Advanced Cabling System |
| ASPS | Advanced Signal Processing System [engl.] |
| ALS | Advanced Launch System [Weltraum] [engl.] |
| ADBS | Advanced Data Broadcasting System [engl.] Verbessertes Funkdatensystem |
| APS | Advanced Production/Photo System [engl.] |
| APTS | Advanced Public Transportation System [engl.] Forschungsvorhaben in den USA |
| ATIS | Advanced Traveller Information System [engl.] |
| ASMP | Advanced System Management Processor [engl.] |
| CLASS | Cumulative and Linguistic Advanced Search System |
| ARCS | Advanced Reconfigurable Computer System [engl.] |
| ATMS | Advanced Traffic Management System [engl.] Entwicklung in den USA |
| ABDS | Advanced Beam Delivery System [engl.] Beamer-Technologie |
| ACCS | Advanced Communication and Control System [engl.] Firmenbezeichnung [Siemens] |
| AVS | Advanced Vertical and short take-off and landing System [engl.] Flugzeugkonzept |
| AFS | Alex/Andrew/Advanced File System [engl.] |
| DISA | Direct Inward System Access |
| ANS | Access Network System |
| RAS | Remote Access System |
| LAS | Library Access System |
| IAS | Information Access System |
| PACS | Personal Access Communication System |
| MACS | Modem Access Control System |
| CAS | Conditional Access System [engl.] Adressierungssystem für den Satellitenfunk |
| DASS | Digital Access Signalling System |
| MEDARS | Medical Access and Retrieval System |
| ACS | Access Control System [engl.] |
| WACS | Wireless Access Communications System |
| DFSA | Direct File System Access |
| CACS | Cable Access Communication System [engl.] Protokoll von Motorola |
| DACS | Digital Access and Cross-connect System |
| BFAS | Basic File Access System [engl.] |
| CABS | Carrier Access Billing System [engl.] Berechnung von Übertragungsleistungen |
| DAVACS | DoE Automated Visitor Access Control System |
| CEK | Content Encryption Key |
| TOC | Table Of Content[s] |
| PIC | Platform for Internet Content |