| Acronym | Sense | Language | Topics |
|---|---|---|---|
| AB3L | Association Béninoise pour la Promotion de Linux et des Logiciels Libres | In French | → Associations |
| ABUL | Association Bordelaise des Utilisateurs de Logiciels libres | In French | → Associations → Software |
| AC3L | Association Camerounaise des utilisateurs de Linux et des Logiciels Libres | In French | → Associations |
| ACM-SIGOPS | Association for Computing Machinery - Special Interest Group on Operating Systems | In English | → Organizations and associations → Computer science |
| ACP | Airline Control Program | In English | → Computer science → Transport by air |
| ADD | Apple Data Detectors | In English | |
| ADFS | Advanced Disc Filing System | In English | |
| AFUL | Association Francophone des Utilisateurs de Linux et des Logiciels Libres (www.aful.org) | In French | → Associations → Programming languages |
| AFUU | Association Française des Utilisateurs d'Unix | In French | → Associations → France |
| AG3L | Association Gabonaise des utilisateurs de Linux et des Logiciels Libres | In French | → Associations |
| AGU3L | Association Grufféenne des Utilisateurs de Linux et des Logiciels Libres | In French | → Associations → Software |
| AI3L | Association Ivoirienne pour Linux et les Logiciels Libres | In French | → Associations |
| AIX | Advanced Interactive eXecutive | In English | |
| ALADIN | Amis de Linux & Amis du Développement sur INternet | In French | → Organizations and associations → Internet |
| ALIS | Association Linux et Informatique Souss | In French | → Associations |
| AMUL | Amicale Malgache des Utilisateurs de logiciels Libres | In French | → Organizations and associations |
| AMULL | Association Malienne des Utilisateurs de Logiciels Libres | In French | → Associations → Computer science |
| AROS | Automotive Robust Operating Services | In English | → Electronics |
| ASF | ACM-SIGOPS France | In French | → Organizations and associations → Computer science |
| AXUL | Association aiXoise des utilisateurs de Linux et des logiciels libres | In French | → Associations → Software |
| BDOS | Basic Disk Operating System | In English | |
| BIOS | Basic Input/Output System | In English | |
| BIOS | Basic Input Output System | In English | |
| BOS | Base Operating System | In English | |
| BSD | Berkeley System Distribution | In English | |
| BSD | Berkeley Software Distribution | In English | |
| BSD | Berkeley Standard Distribution | In English | |
| BTSS | Basic Time Sharing System | In English | |
| CLO | Club Linux Outaouais | In French | → Organizations and associations |
| CNOS | Communication Network Operating System | In English | → Networks, communication |
| COS | Console Operating System | In English | |
| CP/M | Control Program for Microcomputers | In English | |
| CTSS | Compatible Time-Sharing System | In English | |
| CULTe | Club des Utilisateurs de Linux de Toulouse et des environs | In French | → Software |
| DEMOS | Dialogovaya Edinaya Mobilnaya Operatsionnaya Sistema = ДЕМОС | Диалоговая Единая Мобильная Операционная Система | In Russian |
In Russian | |
| DOS | Disk Operating System | In English | |
| ECOS | Experiment Computer Operating System | In English | |
| ELF | EFREI Linux Formation | In French | → Organizations and associations |
| FAT | File Allocation Table | In English | → Files |
| FCOS | Flight Computer Operating System | In English | → Aeronautics, aircraft → Astronautics |
| FCOS | Flight Control Operating System | In English | → Aeronautics, aircraft → Astronautics |
| FFS | (Berkeley) Fast File System | In English | → Files |
| FFS | Flash File System | In English | → Files |
| FFS | (Amiga) Fast File System | In English | → Files |
| G3L | Groupe pour la promotion de GNU/Linux et des Logiciels Libres | In French | → Organizations and associations → Software |
| GCOS | Ground Computer Operating System | In English | |
| GIRLS | Generalized Information Retrieval Language System | In English | → Data |
| GKS | Graphical Kernel System | In English | |
| GPL | Groupe des Pingouins Libres | In French | → Organizations and associations |
| GRAL | Groupement Réunionnais des Amis de Linux | In French | → Organizations and associations |
| GrUB | Groupe d'utilisateurs borains | In French | → Organizations and associations |
| GUL | Groupes d'Utilisateurs de Linux = LUG | Linux Users' Groups | In English |
In French | → Organizations and associations |
| GULAT | Groupe d'utilisateur de Linux de l'Abitibi-Témiscamingue | In French | → Organizations and associations |
| GULiDef | Groupe des Utilisateurs de Linux dans la Défense | In French | → Organizations and associations → Military engineering |
| GULLIVER | Groupe des Utilisateurs de Linux et des Logiciels libres d'Ille et Vilaine et Environs de Rennes | In French | → Software |
| GuLSE | Groupe des Utilisateurs Linux de Saint-Eustache et des environs | In French | → Organizations and associations |
| GULUQ | Groupe d'Utilisateurs Linux de l'Université du Québec | In French | → Organizations and associations → Higher education, universities → Canada |
| GULUS | Groupe d'utilisateurs de Linux de l'Université de Sherbrooke | In French | → Organizations and associations |
| GUML | Groupement des Utilisateurs Mauriciens de Linux | In French | → Organizations and associations |
| HOS | Hybrid Operating System | In English | |
| IDOS | Integrated Display Operating System | In English | |
| ISPF | Interactive System Productivity Facility | In English | → Computer science |
| ITS | Incompatible Timesharing System | In English | |
| JCVM | Java Card Virtual Machine | In English | → Software → Programming languages |
| KLM | Keyboard Layout Manager | In English | |
| KVM | Kernel-based Virtual Machine | In English | → Software |
| LiLoLiPo | Linux et les Logiciels Libres à Pont-Château | In French | → Organizations and associations → Software |
| LinAC | Linux Angoulême Charente | In French | |
| LKD | Linux Kullanıcıları Derneği (www.lkd.org.tr) | In Turkish | → Associations → Turkey |
| LPT | Link PrinTer | In English | |
| LUG | Linux Users' Groups = GUL (look above) |
In English | → Organizations and associations |
| LUGOAL | Linux User Group Of ALgeria (www.lugoal.org) | In English | → Organizations and associations → Algeria |
| LVS | Linux Virtual Server | In English | → Networks, communication |
| MERT | Multi-Environment Real-Time | In English | |
| MFT | Multiprogramming with a Fixed number of Tasks | In English | |
| MIDAS | Multics Intrusion Detection and Alerting System | In English | → Software |
| MLUG | Montreal Linux Users Group | In English | → Organizations and associations |
| MONECS | Monash University Educational Computing System | In English | |
| MOS | Machine Operating System | In English | |
| MRLUG | Montreal Regional Linux Users Group | In English | → Organizations and associations |
| MS-DOS | Microsoft Disk Operating System | In English | |
| MSDOS | Microsoft Disk Operating System | In English | |
| MSDOS | Mass Storage Digital Operating System | In English | |
| MSKLC | Microsoft Keyboard Layout Creator | In English | |
| MTS | Michigan Terminal System | In English | |
| MULTICS | Multiplexed Information and Computing Service | In English | |
| MUSIC/SP | Multi-User System for Interactive Computing / System Product | In English | |
| MVS | Multiple Virtual Storage | In English | |
| MVS/ESA | Multiple Virtual Storage/Enterprise System Architecture | In English | |
| MVS/XA | Multiple Virtual Storage/Extended Architecture | In English | |
| MVT | Multiprogramming with a Variable number of Tasks | In English | |
| OS | Operating System | In English | |
| OSID | Operating System Interface Definition | In English | → Human-computer interaction |
| PauLLA | Pau Logiciels Libres Association | In French | → Associations → Software |
| PC-DOS | Personal Computer Disk Operating System | In English | |
| PLUG | Provence Linux Users Group | In English | |
| PMT | Pre-emptive Multitasking | In English | |
| PPI | Pixel Per Inch | In English | |
| QDOS | Quick and Dirty Operating System | In English | |
| RDOS | Real-Time Disk Operating System | In English | |
| ROSS/V | RSTS/E Operating System Simulator for VAX | In English | |
| RSTS | Resource Sharing Time Sharing System | In English | |
| RTOS | Real-Time Operating System | In English | |
| SALUG | Savoie-Aravis Linux Users Group | In English | → Organizations and associations |
| SCOS | Subsystem Computer Operating System | In English | |
| SE | Système d'Exploitation | In French | |
| SFS | Self-certifying File System | In English | |
| SLS | Softlanding Linux System | In English | |
| SSDT | System Service Dispatch Table | In English | |
| STOICAL | STack Oriented Interactive Compiler Adapted to Linux | In English | → Software |
| TOS | Tape Operating System | In English | |
| TROLL | Troupe Redonnaise Orientée Logiciel Libre | In French | → Software |
| TSS | Time Sharing System | In English | |
| TTX | TinyOS Technology Exchange | In English | → Congresses → Electronics |
| UUCP | Unix-to-Unix Copy | In English | → Software |
| WOS | Web Operating System | In English | → Internet |
| WPF | Windows Presentation Foundation | In English | |
| WPF/E | Windows Presentation Foundation Everywhere | In English | |
| WSL | Windows Subsystem for Linux | In English | |
| XPCOM | Cross Platform Component Object Model | In English | → Software |
| XPFE | Cross Platform Front End | In English | → Software |
| ДЕМОС | Диалоговая Единая Мобильная Операционная Система = DEMOS (look above) |
In Russian | |
| МНОС | МобильНая Операционная Система | In Russian |