| 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 |
| AFUL | Association Francophone des Utilisateurs de Linux et des Logiciels Libres | In French | → Programming languages → Organizations and associations |
| AFUU | Association Francaise des Utilisateurs d'Unix | In French | → Associations |
| 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 |
| 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 |
| AXUL | Association aiXoise des utilisateurs de Linux et des logiciels libres | In French | → Associations → Software |
| BIOS | Basic Input/Output System | In English | |
| BSD | Berkeley System Distribution | In English | |
| BSD | Berkeley Software Distribution | In English | |
| CLO | Club Linux Outaouais | In French | → Organizations and associations |
| COS | Console Operating System | In English | |
| CULTe | Club des Utilisateurs de Linux de Toulouse et des environs | In French | → Software |
| 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 | |
| FCOS | Flight Computer Operating System | In English | → Aeronautics, aircraft → Spaceflight engineering, astronautics |
| FCOS | Flight Control Operating System | In English | → Aeronautics, aircraft → Spaceflight engineering, astronautics |
| 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 |
| 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 | |
| KLM | Keyboard Layout Manager | In English | |
| 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 | In Turkish | |
| LUG | Linux Users' Groups = GUL (look above) |
In English | → Organizations and associations |
| LUGOAL | Linux User Group Of ALgeria | In English | → Organizations and associations |
| LVS | Linux Virtual Server | In English | → Networks, communication |
| MLUG | Montreal Linux Users Group | In English | → Organizations and associations |
| MRLUG | Montreal Regional Linux Users Group | In English | → Organizations and associations |
| MS-DOS | Microsoft Disk Operating System | In English | |
| MSDOS | Mass Storage Digital Operating System | In English | |
| MSDOS | Microsoft Disk Operating System | In English | |
| MSKLC | Microsoft Keyboard Layout Creator | 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 |
| PLUG | Provence Linux Users Group | In English | |
| QDOS | Quick and Dirty Operating System | In English | |
| RDOS | Real-Time Disk 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 | |
| SLS | Softlanding Linux System | In English | |
| STOICAL | STack Oriented Interactive Compiler Adapted to Linux | In English | → Software |
| TROLL | Troupe Redonnaise Orientée Logiciel Libre | In French | → Software |
| WPF | Windows Presentation Foundation | In English | |
| WPF/E | Windows Presentation Foundation Everywhere | In English | |
| XPCOM | Cross Platform Component Object Model | In English | → Software |
| XPFE | Cross Platform Front End | In English | → Software |