| ODDL | On-Board Digital Data Load | In English | → Data |
| ODDP | Object-Dependent Data Processor | In English | → Hardware → Data |
| ODE | Orchestration Director Engine | In English | → Software |
| ODE | Open Dynamics Engine (www.ode.org) | In English | → Software → Image processing → Computer simulation |
| ODF | Output Data Formatter | In English | → Software → Data |
| ODF | Open Document Format | In English | → Data → Document processing |
| ODR | Output Data Redundancy | In English | → Data |
| ODRC | Orbiter Data Reduction Center | In English | → Data → Spaceflight engineering, astronautics |
| ODU | Output Display Unit | In English | → Human-computer interaction |
| ÖFAI | Österreichisches Forschungsinstitut für Artificial Intelligence (www.ofai.at) | In German | → Research institutes → Artificial intelligence |
| OFDM | Orthogonal Frequency Division Multiplexing | In English | → Networks, communication → Telecommunications |
| OFDS | Orbiter Flight Dynamic Simulator | In English | → Computer simulation → Spaceflight engineering, astronautics |
| OFTDS | Orbital Flight Test Data System | In English | → Data → Spaceflight engineering, astronautics |
| OGC | Open Geospatial Consortium | In English | → Organizations and associations → Geodesy, cartography |
| ÖGIG | Österreichische Gesellschaft für Informatikgeschichte | In German | → History |
| OI | Ordinateur Individuel | In French | → Serial publications, periodicals |
| OI | Olimpiada Informatyczna | In Polish | |
| OIA | Orbiter Interface Adapter | In English | → Human-computer interaction → Spaceflight engineering, astronautics |
| OIL | Ontology Inference Layer | In English | → Programming languages → Libraries |
| OKBC | Open Knowledge Base Connectivity | In English | |
| OLAP | On Line Analytical Processing | In English | → Knowledge management → Data |
| OLDB | On-Line Data Bank | In English | → Data |
| OLE | Object Linking and Embedding | In English | → Software |
| OLPC | One Laptop Per Child | In English | → Hardware |
| OLTP | On Line Transaction Processing | In English | → Data |
| OMAS | Operations Management Application Software | In English | → Software → Management |
| OMG | Object Management Group | In English | → Organizations and associations → Software |
| OMNSH | Observatoire des Mondes Numériques en Sciences Humaines (www.omnsh.org) | In French | → Organizations and associations → Social sciences |
| OMR | Optical Mark Recognition | In English | → Writing systems → Computer-based techniques |
| OMT | Object-Modeling Technique | In English | → Software |
| OntoUCP | Ontology-based Unified Communication Protocol | In English | → Programming languages |
| OntoUCP | Ontology based Unified Communication Protocol | In English | → Software → Networks, communication |
| OPML | Outline Processor Markup Language | In English | → Programming languages |
| OPPTIC | Organisation de Professionnels pour la Promotion des TIC en région Languedoc-Roussillon | In French | → Networks, communication → Organizations and associations → Telecommunications |
| OPSDB | Operations Data Base | In English | → Data |
| OPSDBA | Operations Data Base Administrator | In English | → Data → Management |
| OPSIS | Observation et Prospective sur la Société de l'Information et ses Services | In French | → Telecommunications |
| ORAM | Output Random Access Memory | In English | → Memories |
| ORAP | Organisation Associative du Parallélisme | In French | → Organizations and associations |
| ORB | Object Request Broker | In English | → Networks, communication |
| ORC | Optical Character Recognition = ROC | Reconnaissance Optique de Caractères | In French |
In English | → Writing systems → Computer-based techniques |
| ORCHIS | Oak Ridge Computerized Hierarchical Information System | In English | → Knowledge management |
| ORDI | Ontology Representation and Data Integration | In English | → Software |
| ORRCA | Ontario Research Centre for Computer Algebra | In English | → Computer-based techniques → Algebra |
| ORSDI | Oak Ridge Selective Dissemination of Information | In English | → Knowledge management |
| OS | Operating System | In English | → Operating systems |
| OS | Operating Software | In English | → Software |
| OS3B | Open Software Blanc Bleu Belge | In French | → Organizations and associations → Software |
| OSCF | Operations Support Computing Facility | In English | |
| OSCR | Orbiter Software Change Request | In English | → Software → Spaceflight engineering, astronautics |
| OSDL | Open Source Development Labs | In English | → Software |
| OSDL | Open Source Development Lab | In English | → Software |
| OSE | Open System Environment | In English | |
| OSF | Open Software Foundation | In English | → Foundations → Software |
| OSI | Open Source Initiative | In English | → Software |
| OSID | Operating System Interface Definition | In English | → Operating systems → Human-computer interaction |
| OSIM | Open Source In Morocco | In English | → Organizations and associations → Software |
| OSPF | Open Shortest Path First | In English | → Internet |
| OSRBD | Operational Software Reliability Benchmark Development | In English | → Software |
| OSTDS | Office of Space Tracking and Data Systems | In English | → Data → Spaceflight engineering, astronautics |
| OTDA | Office of Tracking And Data Acquisition | In English | → Data |
| OWL | Web Ontology Language | In English | → Data → Programming languages |
| P&D | Panels and Displays | In English | → Human-computer interaction |
| P&I | Performance and Interface | In English | → Human-computer interaction |
| P2P | Peer-to-Peer | In English | → Networks, communication |
| P3P | Platform for Privacy Preferences | In English | → Networks, communication → Telecommunications |
| PADSIM | Probabilistic Adaptive Simulation Model | In English | → Computer simulation |
| PAIR | Portal to Asian Internet Resources | In English | → Libraries → Networks, communication |
| PAMI | Pattern Analysis and Machine Intelligence | In English | → Document processing |
| PASO | Pattern-Oriented Software Architecture | In English | → Software |
| PASS | Primary Avionics Software System | In English | → Software → Aeronautics, aircraft |
| PASTISS | Professional Analysis Software Tool for Inflatable Space Structures | In English | → Software → Mechanical engineering |
| PauLLA | Pau Logiciels Libres Association | In French | → Associations → Software → Operating systems |
| PBB | Provider Backbone Bridge | In English | → Networks, communication → Telecommunications |
| PBB-TE | Provider Backbone Bridge - Traffic Engineering | In English | → Networks, communication → Telecommunications |
| PBBN | Provider Backbone Bridge Network | In English | → Networks, communication → Telecommunications |
| PBEB | Provider Backbone Edge Bridge | In English | → Networks, communication → Telecommunications |
| PBIC | Programmable Buffer Interface Card | In English | → Hardware → Software |
| PBIM | Programmable Buffer Interface Module | In English | → Software → Human-computer interaction |
| PBS | Portable Batch System | In English | → Software → Networks, communication |
| PBT | Provider Backbone Transport | In English | → Networks, communication → Telecommunications |
| PC | Personal Computer = PK | Persoanlike kompjûter | In Frisian |
In English | → Hardware |
| PC&PM | Program Control and Performance Management | In English | → Software |
| PCDATA | Parsed Character Data | In English | → Data |
| PCGI | Perl Common Gateway Interface | In English | → Programming languages → Networks, communication |
| PCI | Peripheral Controller Interface | In English | → Human-computer interaction |
| PCI | Peripheral Component Interconnect | In English | → Hardware → Telecommunications |
| PCI-E | Peripheral Component Interconnect Express | In English | → Electronics |
| PCL | Programming Checklist | In English | → Software |
| PCM | Pulse Code Modulation | In English | → Computer-based techniques → Music |
| PCMCIA | Personal Computer Memory Card International Association | In English | → Associations → Memories |
| PCMU | Programmable Control and Monitor Unit | In English | |
| PCRE | Perl-Compatible Regular Expression | In English | → Software |
| PCS | Professional Clinical Software | In English | → Software → Medicine |
| PDA | Personal Digital Assistant | In English | → Hardware → Telecommunications |
| Portable Document Format | In English | → Programming languages → Data → Document processing |
|
| PDH | Plesiochronous Digital Hierarchy | In English | → Networks, communication → Telecommunications |
| PDM | Processor Data Monitor | In English | → Human-computer interaction → Data |
| PDU | Protocol Data Unit | In English | → Networks, communication |
| PE | Parity Error | In English | |
| PERL | Practical Extraction and Report Language | In English | → Programming languages |
| PERM | Programmgesteuerte Elektronische Rechenanlage | In German | → Hardware |
| PESSL | Parallel Engineering and Scientific Subroutine Library | In English | → Programming languages → Mathematics and natural sciences → Engineering, technology |
| PET | Personal Electronic Transactor | In English | → Hardware |
| PET | Persona-Enabling Toolkit | In English | → Networks, communication → Telecommunications |
| PETSCII | PET Standard Code of Information Interchange | In English | |
| PFS | Primary Flight Software | In English | → Software → Aeronautics, aircraft → Spaceflight engineering, astronautics |
| PGC | Progiciel de Gestion du Contenu | In French | → Software → Knowledge management |
| PGI | Progiciel de Gestion Intégrée | In English | → Software |
| PGML | Precision Graphics Markup Language | In English | → Programming languages → Image processing |
| PGSC | Payload and General-Support Computer | In English | → Hardware |
| PHAROS | Platform for searcH of Audiovisual Resources across Online Spaces (www.pharos-audiovisual-search.eu) | In English | → Networks, communication → Computer-based techniques |
| PHB | Per Hop Behavior | In English | → Networks, communication → Telecommunications |
| PHP | PHP Hypertext Preprocessor | In English | → Programming languages → Networks, communication |
| PHP | Personal Home Page | In English | → Programming languages → Networks, communication |
| PI&A | Personnel Identification and Authentication | In English | → 00495 → Labour, labour economics |
| PICC | Payload Interface Control Computer | In English | → Hardware → 0055 |
| PICP | Program Interface Control Plan | In English | → Human-computer interaction |
| PICS | Platform for Internet Content Selection | In English | → Internet |
| PIDS | Portable Image Display System | In English | → Human-computer interaction |
| PINCH | Payload Integration Nominal Cost Hardware | In English | → Hardware |
| PING | Packet Internet Gopher | In English | → Networks, communication |
| PIRN | Preliminary Interface Revision Notice | In English | → Human-computer interaction |
| PIRN | Proposed Interface Revision Notice | In English | → Human-computer interaction |
| PK | Persona Komputilo | In Esperanto | → Hardware |
| PK | Persoanlike kompjûter = PC (look above) |
In Frisian | → Hardware |
| PKD | Programmable Keyboard and Display | In English | → Human-computer interaction |
| PKI | Public Key Infrastructure | In English | |
| PLA | Programmable Logic Array | In English | → Hardware → Electronics |
| PLD | Programmable Logic Device | In English | → Hardware → Electronics |
| PLDI | Programming Language Design and Implementation | In English | → Programming languages |
| PLIMHR | Payload Integration Management Hardware Review | In English | → Hardware → Management |
| PLUG | Provence Linux Users Group | In English | → Operating systems |
| PM | Performance Monitor | In English | → Human-computer interaction → Management |
| PMA | Performance Monitor Annunciator | In English | → Human-computer interaction → Management |
| PMAC | Portable Multipurpose Applications Console | In English | → Software → Human-computer interaction |
| PMAD | Performance Monitor Annunciation Driver | In English | → Human-computer interaction → Management |
| PMAP | Performance Monitor Annunciation Panel | In English | → Human-computer interaction → Management |
| PMF | Performance Monitor Function | In English | → Human-computer interaction → Management |
| PMHL | Preferred Measurement Hardware List | In English | → Hardware |
| PMIA | Parallel Multiplexer Interface Adapter | In English | → Human-computer interaction |
| PMP | Prelaunch Monitor Program | In English | → Human-computer interaction → Spaceflight engineering, astronautics |
| PMSI | Programme de Médicalisation des Systèmes d'Information | In French | → Knowledge management → Data → Medicine |
| PNI | Picture Network International | In English | → Data → Graphical processing → Image processing |
| POD | Parameter Override Display | In English | → Human-computer interaction |
| POJO | Plain Old Java Object | In English | → Programming languages |
| POP | Presentation Oriented Publishing | In English | → Document processing |
| POP | Post Office Protocol | In English | → Networks, communication |
| POSIX | Portable Operating System Interface | In English | → Software → Human-computer interaction |
| PPC | Preprocessing Center | In English | |
| PPCP | Postprocessing Computer Program | In English | → Software |
| PPM | Perl Package Manager | In English | → Software |
| PPP | Point-to-Point Protocol | In English | → Networks, communication |
| PRAI | Pattern Recognition and Artificial Intelligence | In English | → Software |
| PREMIA | Pattern Recognition and Machine Intelligence Association | In English | → Associations → Artificial intelligence → Computer-based techniques |
| PRIP | Pattern Recognition and Image Processing | In English | → Graphical processing → Image processing |
| PRISM | Pacific Regional Information SysteM | In English | → Telecommunications |
| PRISMA | Productique et Informatique des Systèmes Manufacturiers | In French | → Computer-based techniques → Mechanical engineering |
| PROGRESS | Programme for Research on Embedded Systems & Software | In English | → Software → Electronics |
| PROLOG | PROgrammation LOGique | In French | → Programming languages |
| PROM | Programmable Read-Only Memory | In English | → Memories |
| PRPS | Programming Requirements Process Specification | In English | → Software |
| PS | PostScript | In English | → Programming languages → Document processing |
| PSC | Pittsburgh Supercomputing Center | In English | |
| PSCN | Program Support Communications Network | In English | → Networks, communication → Telecommunications |
| PSDN | Packet Switched Data Network | In English | → Networks, communication |
| PSK | Phase Shift Key | In English | → Human-computer interaction |
| PSL | Program Statement Language | In English | → Programming languages |
| PSO | Phantasy Star Online | In English | → Software → Entertainment |
| PSP | Programmable Signal Processor | In English | → Software → Telecommunications |
| PSP | PlayStation Portable | In English | → Hardware → Entertainment |
| PSWWWVL | Pacific Studies WWW Virtual Library | In English | → Internet → Libraries → Area studies |
| PUZ | Prozesatzeko Unitate Zentral | In Basque | → Hardware |
| PWA | Private Write Area | In English | → Memories |
| QBIC | Query By Image Content | In English | → Image processing |
| QDOS | Quick and Dirty Operating System | In English | → Operating systems |
| QES | Qwam E-content Server | In English | → Networks, communication → Libraries |
| QLDS | Quick-Look Data Station | In English | → Data |
| QOM | Quick Ontology Mapping | In English | → Software |
| QUIC | Quality Data Information and Control | In English | → Quality management → Data |
| R@S | Réseau Associatif et Syndical | In French | → Networks, communication |
| RAAP | Red Académica Peruana | In Spanish | → Higher education, universities → Telecommunications |
| RACF | Resource Access Control Facility | In English | → Software |
| RADOP | Radiator Optimization Computer Code | In English | → Software |
| RAGIE | Red Avanzada Guatemalteca para la Investigación y Educación | In Spanish | → Education → Mathematics and natural sciences → Telecommunications |
| RAICES | Red Avanzada de Investigación, Ciencia y Educación Salvadoreña | In Spanish | → Education → Mathematics and natural sciences → Telecommunications |
| RAID | Redundant Array of Independent Disks | In English | → Memories |
| RAID | Redundant Array of Independant Disks | In English | → Memories |
| RAM | Random Access Memory | In English | → Memories |
| RAMDAC | Random Access Memory Digital to Analog Converter | In English | → Memories |
| RAP | Reconnaissance Automatique de la Parole = ASR | Automatic Speech Recognition | In English |
In French | → Computer-based techniques → Linguistics |
| RAPRIA | Russian Federation Association for Pattern Recognition and Image Analysis | In English | → Organizations and associations → Graphical processing → Image processing |
| RARP | Reverse Address Resolution Protocol | In English | → Internet |
| RASMUS | Remote Accessible Software configurable Multi-channel Ultrasound Sampling system | In English | → Software → Diagnostics |
| RAU | Red Académica Uruguaya | In Spanish | → Higher education, universities → Telecommunications |
| RAX | Remote Access Computing System | In English | → Hardware |
| RAX | Remote Access Terminal | In English | → Human-computer interaction |
| RCP | Rémunération pour Copie Privée | In French | → Software → Cinema, movies |
| RCP | Rich Client Platform | In English | → Software |
| RCS | Revision Control System | In French | → Software |