This is a list of computing and IT acronyms, initialisms and abbreviations.
- 1GL—First-Generation Programming Language
- 1NF—First Normal Form
- 10B2—10BASE-2
- 10B5—10BASE-5
- 10B-F—10BASE-F
- 10B-FB—10BASE-FB
- 10B-FL—10BASE-FL
- 10B-FP—10BASE-FP
- 10B-T—10BASE-T
- 100B-FX—100BASE-FX
- 100B-TX—100BASE-TX
- 100BVG—100BASE-VG
- 286—Intel 80286 processor
- 2B1Q—2 Binary 1 Quaternary
- 2FA—Two-factor authentication
- 2GL—Second-Generation Programming Language
- 2NF—Second Normal Form
- 3GL—Third-Generation Programming Language
- 3GPP—3rd Generation Partnership Project – 3G comms
- 3GPP2—3rd Generation Partnership Project 2
- 3NF—Third Normal Form
- 386—Intel 80386 processor
- 486—Intel 80486 processor
- 4B5BLF—4-bit 5-bit Local Fiber
- 4GL—Fourth-Generation Programming Language
- 4NF—Fourth Normal Form
- 5GL—Fifth-Generation Programming Language
- 5NF—Fifth Normal Form
- 6NF—Sixth Normal Form
- 8B10BLF—8-bit 10-bit Local Fiber
- 802.11—Wireless LAN
- B2B—Business-to-Business
- B2C—Business-to-Consumer
- B2E—Business-to-Employee
- BAL—Basic Assembly Language
- BAM—Block Availability Map
- Bash—Bourne-again shell
- BASIC—Beginner's All-Purpose Symbolic Instruction Code
- BBP—Baseband Processor
- BBS—Bulletin Board System
- BC—Business Continuity
- BCC—Blind Carbon Copy
- BCD—Binary Coded Decimal
- BCD—Boot Configuration Data
- BCNF—Boyce–Codd normal form
- BCP—Business Continuity Planning
- BCP—Best Current Practice
- BE—Backend
- BEEP—Blocks Extensible Exchange Protocol
- BER—Bit Error Rate
- BFD—Bidirectional Forwarding Detection
- BFD—Binary File Descriptor
- BFS—Breadth-First Search
- BFT—Byzantine Fault Tolerant
- BGP—Border Gateway Protocol
- BI—Business Intelligence
- BiDi—Bi-Directional
- bin—binary
- BINAC—Binary Automatic Computer
- BIND—Berkeley Internet Name Domain
- BIOS—Basic Input Output System
- BJT—Bipolar Junction Transistor
- bit—binary digit
- Blob—Binary large object
- Blog—Web Log
- BMP—Basic Multilingual Plane
- BNC—Baby Neill Constant
- BOINC—Berkeley Open Infrastructure for Network Computing
- BOM—Byte Order Mark
- BOOTP—Bootstrap Protocol
- BPDU—Bridge Protocol Data Unit
- BPEL—Business Process Execution Language
- BPL—Broadband over Power Lines
- BPM—Business Process Management
- BPM—Business Process Modeling
- bps—bits per second
- BRM—Business Reference Model
- BRMS—Business Rule Management System
- BRR—Business Readiness Rating
- BRS—Broadband Radio Service
- BSA—Business Software Alliance
- BSB—Backside Bus
- BSD—Berkeley Software Distribution
- BSoD—Blue Screen of Death
- BSS—Block Started by Symbol
- BT—BitTorrent
- BT—Bluetooth
- B TAM—Basic Telecommunications Access Method
- BW—Bandwidth
- BYOD—Bring Your Own Device
- Byte—By eight (group of 8 bits)
- DAC—Digital-To-Analog Converter
- DAC—Discretionary Access Control
- DAL—Database Abstraction Layer
- DAO—Data Access Object
- DAO—Data Access Objects
- DAO—Disk-At-Once
- DAP—Directory Access Protocol
- DARPA—Defense Advanced Research Projects Agency
- DAS—Direct Attached Storage
- DAT—Digital Audio Tape
- DB—Database
- DSKT—Desktop
- DBA—Database Administrator
- DBCS—Double Byte Character Set
- DBMS—Database Management System
- DCC—Direct Client-to-Client
- DCCP—Datagram Congestion Control Protocol
- DCCA—Debian Common Core Alliance
- DCL—Data Control Language
- DCS—Distributed Control System
- DCMI—Dublin Core Metadata Initiative
- DCOM—Distributed Component Object Model
- DD—Double Density
- DDE—Dynamic Data Exchange
- DDL—Data Definition Language
- DDoS—Distributed Denial of Service
- DDR—Double Data Rate
- DEC—Digital Equipment Corporation
- DES—Data Encryption Standard
- dev—development
- DFA—Deterministic Finite Automaton
- DFD—Data Flow Diagram
- DFS—Depth-First Search
- DFS—Distributed File System
- DGD—Dworkin's Game Driver
- DHCP—Dynamic Host Configuration Protocol
- DHTML—Dynamic Hypertext Markup Language
- DIF—Data Integrity Field
- DIMM—Dual Inline Memory Module
- DIN—Deutsches Institut für Normung
- DIP—Dual In-line Package
- DISM—Deployment Image and Service Management Tool
- DIVX—Digital Video Express
- DKIM—Domain Keys Identified Mail
- DL—Download
- DLL—Dynamic Link Library
- DLNA—Digital Living Network Alliance
- DMA—Direct Memory Access
- DMCA—Digital Millennium Copyright Act
- DMI—Direct Media Interface
- DML—Data Manipulation Language
- DML—Definitive Media Library
- DMR—Dennis M. Ritchie
- DMZ—Demilitarized Zone
- DN—Distinguished Name
- DND—Drag-and-Drop
- DNS—Domain Name System
- DOA—Dead on Arrival
- DOCSIS—Data Over Cable Service Interface Specification
- DOM—Document Object Model
- DORA—Discover, Offer, Request, Acknowledge
- DoS—Denial of Service
- DOS—Disk Operating System
- DP—Dot Pitch
- DPC—Deferred Procedure Call
- DPI—Deep Packet Inspection
- DPI—Dots Per Inch
- DPMI—DOS Protected Mode Interface
- DPMS—Display Power Management Signaling
- DR—Disaster Recovery
- DRAM—Dynamic Random-Access Memory
- DR-DOS—Digital Research – Disk Operating System
- DRI—Direct Rendering Infrastructure
- DRM—Digital Rights Management
- DRM—Direct Rendering Manager
- DSA—Digital Signature Algorithm
- DSDL—Document Schema Definition Languages
- DSDM—Dynamic Systems Development Method
- DSL—Digital Subscriber Line
- DSL—Domain-Specific Language
- DSLAM—Digital Subscriber Line Access Multiplexer
- DSN—Database Source Name
- DSN—Data Set Name
- DSP—Digital Signal Processor
- DSSSL—Document Style Semantics and Specification Language
- DTD—Document Type Definition
- DTE—Data Terminal Equipment or data transfer rate
- DTO—Data Transfer Object
- DTP—Desktop Publishing
- DTR—Data Terminal Ready or Data transfer rate
- DVD—Digital Versatile Disc or Digital Video Disc
- DVD-R—DVD-Recordable
- DVD-ROM—DVD-Read-Only Memory
- DVD-RW—DVD-Rewritable
- DVI—Digital Visual Interface
- DVR—Digital Video Recorder
- DW—Data Warehouse
- EAI—Enterprise Application Integration
- EAP—Extensible Authentication Protocol
- EAS—Exchange ActiveSync
- EBCDIC—Extended Binary Coded Decimal Interchange Code
- EBML—Extensible Binary Meta Language
- ECC—Elliptic Curve Cryptography
- ECMA—European Computer Manufacturers Association
- ECN—Explicit Congestion Notification
- ECOS—Embedded Configurable Operating System
- ECRS—Expense and Cost Recovery System
- ECS—Entity-Component-System
- EDA—Electronic Design Automation
- EDGE—Enhanced Data rates for GSM Evolution
- EDI—Electronic Data Interchange
- EDO—Extended Data Out
- EDSAC—Electronic Delay Storage Automatic Calculator
- EDVAC—Electronic Discrete Variable Automatic Computer
- EEPROM—Electronically Erasable Programmable Read-Only Memory
- EFF—Electronic Frontier Foundation
- EFI—Extensible Firmware Interface
- EFM—Eight-to-Fourteen Modulation
- EFM—Ethernet in the First Mile
- EFS—Encrypting File System
- EGA—Enhanced Graphics Array
- E-mail—Electronic mail
- EGP—Exterior Gateway Protocol
- eID—electronic ID card
- EIDE—Enhanced IDE
- EIGRP—Enhanced Interior Gateway Routing Protocol
- EISA—Extended Industry Standard Architecture
- ELF—Extremely Low Frequency
- ELF—Executable and Linkable Format
- ELM—ELectronic Mail
- EMACS—Editor MACroS
- EMS—Expanded Memory Specification
- ENIAC—Electronic Numerical Integrator And Computer
- EOF—End of File
- EOL—End of Life
- EOL—End of Line
- EOM—End of Message
- EOS—End of Support
- EPIC—Explicitly Parallel Instruction Computing
- EPROM—Erasable Programmable Read-Only Memory
- ERD—Entity–Relationship Diagram
- ERM—Entity–Relationship Model
- ERP—Enterprise Resource Planning
- eSATA—external SATA
- ESB—Enterprise service bus
- ESCON—Enterprise Systems Connection
- ESD—Electrostatic Discharge
- ESI—Electronically Stored Information
- ESR—Eric Steven Raymond
- ETL—Extract, Transform, Load
- ETW—Event Tracing for Windows
- EUC—Extended Unix Code
- EULA—End User License Agreement
- EWMH—Extended Window Manager Hints
- EXT—EXTended file system
- ETA—Estimated Time of Arrival
- FAP—FORTRAN Assembly Program
- FASM—Flat ASseMbler
- FAT—File Allocation Table
- FAQ—Frequently Asked Questions
- FBDIMM—Fully Buffered Dual Inline Memory Module
- FC-AL—Fibre Channel Arbitrated Loop
- FCB—File Control Block
- FCS—Frame Check Sequence
- FDC—Floppy-Disk Controller
- FDS—Fedora Directory Server
- FDD—Frequency-Division Duplexing
- FDD—Floppy Disk Drive
- FDDI—Fiber Distributed Data Interface
- FDM—Frequency-Division Multiplexing
- FDMA—Frequency-Division Multiple Access
- FE—Frontend
- FEC—Forward Error Correction
- FEMB—Front-End Motherboard
- FET—Field Effect Transistor
- FHS—Filesystem Hierarchy Standard
- FICON—FIber CONnectivity
- FIFO—First In First Out
- FIPS—Federal Information Processing Standards
- FL—Function Level
- FLAC—Free Lossless Audio Codec
- FLOPS—FLoating-Point Operations Per Second
- FLOSS—Free/Libre/Open-Source Software
- FMC—Fixed Mobile Convergence "Mobile UC or Unified Communications over Wireless"
- FOLDOC—Free On-line Dictionary of Computing
- FORTRAN—Formula Translation
- FOSDEM—Free and Open-source Software Developers' European Meeting
- FOSI—Formatted Output Specification Instance
- FOSS—Free and Open-Source Software
- FP—Function Programming
- FP—Functional Programming
- FPGA—Field Programmable Gate Array
- FPS—Floating Point Systems
- FPU—Floating-Point Unit
- FRU—Field-Replaceable Unit
- FS—File System
- FSB—Front-Side Bus
- fsck—File System Check
- FSF—Free Software Foundation
- FSM—Finite State Machine
- FTTC—Fiber To The Curb
- FTTH—Fiber To The Home
- FTTP—Fiber To The Premises
- FTP—File Transfer Protocol
- FQDN—Fully Qualified Domain Name
- FUD—Fear Uncertainty Doubt
- FWS—Folding White Space
- FXP—File eXchange Protocol
- FYI—For Your Information
- G11N—Globalization
- Gas—GNU Assembler
- Gb—Gigabit
- GB—Gigabyte
- Gbps—Gigabits per second
- GCC—GNU Compiler Collection
- GCJ—GNU Compiler for Java
- GCP—Google Cloud Platform
- GCR—Group Coded Recording
- GDB—GNU Debugger
- GDI—Graphics Device Interface
- GFDL—GNU Free Documentation License
- GIF—Graphics Interchange Format
- GIGO—Garbage In, Garbage Out
- GIMP—GNU Image Manipulation Program
- GIMPS—Great Internet Mersenne Prime Search
- GIS—Geographic Information System
- GLUT—OpenGL Utility Toolkit
- GML—Geography Markup Language
- GNOME—GNU Network Object Model Environment
- GNU—GNU's Not Unix
- GOMS—Goals, Operators, Methods, and Selection rules
- GPASM—GNU PIC ASseMbler
- GPFS—General Parallel File System
- GPG—GNU Privacy Guard
- GPGPU—General-Purpose Computing on Graphics Processing Units
- GPIB—General-Purpose Instrumentation Bus
- GPL—General Public License
- GPL—General-Purpose Language
- GPRS—General Packet Radio Service
- GPT—GUID Partition Table
- GPU—Graphics Processing Unit
- GRUB—Grand Unified Boot-Loader
- GERAN—GSM EDGE Radio Access Network
- GSM—Global System for Mobile Communications
- GTK/GTK+—GIMP Toolkit[1]
- GUI—Graphical User Interface
- GUID—Globally Unique IDentifier
- GWT—Google Web Toolkit
- HA—High availability
- HAL—Hardware Abstraction Layer
- HASP—Houston Automatic Spooling Priority
- HBA—Host Bus Adapter
- HCI—Human—Computer Interaction
- HD—High Density
- HDD—Hard Disk Drive
- HCL—Hardware Compatibility List
- HD DVD—High Definition DVD
- HDL—Hardware Description Language
- HDMI—High-Definition Multimedia Interface
- HECI—Host Embedded Controller Interface
- HF—High Frequency
- HFS—Hierarchical File System
- HHD—Hybrid Hard Drive
- HID—Human Interface Device
- HIG—Human Interface Guidelines
- HIRD—Hurd of Interfaces Representing Depth
- HLASM—High Level ASseMbler
- HLS—HTTP Live Streaming
- HMA—High Memory Area
- HP—Hewlett-Packard
- HPC—High-Performance Computing
- HPFS—High Performance File System
- HSDPA—High-Speed Downlink Packet Access
- HTC—High-Throughput Computing
- HSM—Hierarchical Storage Management
- HT—Hyper Threading
- HTM—Hierarchical Temporal Memory
- HTML—Hypertext Markup Language
- HTTP—Hypertext Transfer Protocol
- HTTPd—Hypertext Transport Protocol Daemon
- HTTPS—HTTP Secure
- HTX—HyperTransport eXpansion
- HURD—Hird of Unix-Replacing Daemons
- HVD—Holographic Versatile Disc
- Hz—Hertz
- I²C—Inter-Integrated Circuit
- I²S—Integrated Interchip Sound
- I18N—Internationalization
- IANA—Internet Assigned Numbers Authority
- IaaS—Infrastructure as a Service
- IaC—Infrastructure as Code
- iBCS—Intel Binary Compatibility Standard
- IBM—International Business Machines
- IC—Integrated Circuit
- ICANN—Internet Corporation for Assigned Names and Numbers
- ICE—In-Circuit Emulator
- ICE—Intrusion Countermeasure Electronics
- ICH—I/O Controller Hub
- ICMP—Internet Control Message Protocol
- ICP—Internet Cache Protocol
- ICS—Internet Connection Sharing
- ICT—Information and Communication Technology
- IDE—Integrated Development Environment
- IDE—Integrated Drive Electronics
- IDF—Intermediate Distribution Frame
- IDF—Intermediate Data Format
- IDL—Interactive Data Language
- IDL—Interface Definition Language
- IdP—Identity Provider (cybersecurity)
- IDS—Intrusion Detection System
- IE—Internet Explorer
- IEC—International Electrotechnical Commission
- IEEE—Institute of Electrical and Electronics Engineers
- IETF—Internet Engineering Task Force
- IFL—Integrated Facility for Linux
- IGMP—Internet Group Management Protocol
- IGRP—Interior Gateway Routing Protocol
- IHV—Independent Hardware Vendor
- IIOP—Internet Inter-Orb Protocol
- IIS—Internet Information Services
- IKE—Internet Key Exchange
- IL—Intermediate Language
- IM—Instant Message or Instant Messaging
- IMAP—Internet Message Access Protocol
- IME—Input Method Editor
- INFOSEC—Information Systems Security
- I/O—Input/output
- IoT—Internet of Things
- IP—Intellectual Property
- IP—Internet Protocol
- IPAM—IP Address Management
- IPC—Inter-Process Communication
- IPL—Initial Program Load
- IPMI—Intelligent Platform Management Interface
- IPO—Inter Procedural Optimization
- IPP—Internet Printing Protocol
- IPS—In-Plane Switching
- IPS—Instructions Per Second
- IPS—Intrusion Prevention System
- IPsec—Internet Protocol security
- IPTV—Internet Protocol Television
- IPv4—Internet Protocol version 4
- IPv6—Internet Protocol version 6
- IPX—Internetwork Packet Exchange
- IR—Intermediate Representation
- IRC—Internet Relay Chat
- IrDA—Infrared Data Association
- IRI—Internationalized Resource Identifier
- IRP—I/O Request Packet
- IRQ—Interrupt Request
- IS—Information Systems
- IS-IS—Intermediate System to Intermediate System
- ISA—Industry Standard Architecture
- ISA—Instruction Set Architecture
- ISAM—Indexed Sequential Access Method
- ISATAP—Intra-Site Automatic Tunnel Addressing Protocol
- ISC—Internet Storm Center
- iSCSI—Internet Small Computer System Interface
- ISDN—Integrated Services Digital Network
- ISO—International Organization for Standardization
- iSNS—Internet Storage Name Service
- ISP—Internet Service Provider
- ISPF—Interactive System Productivity Facility
- ISR—Interrupt Service Routine
- ISV—Independent Software Vendor
- IT—Information Technology
- ITIL—Information Technology Infrastructure Library
- ITL—Interval Temporal Logic
- ITU—International Telecommunication Union
- IVR(S)—Interactive Voice Response (System)
- J2EE—Java 2 Enterprise Edition
- J2ME—Java 2 Micro Edition
- J2SE—Java 2 Standard Edition
- JAXB—Java Architecture for XML Binding
- JAX-RPC—Jakarta XML (formerly Java XML) for Remote Procedure Calls
- JAXP—Java API for XML Processing
- JBOD—Just a Bunch of Disks
- JCE— Java Cryptography Extension
- JCL—Job Control Language
- JCP—Java Community Process
- JDBC—Java Database Connectivity
- JDK—Java Development Kit
- JEE—Java Enterprise Edition
- JES—Job Entry Subsystem
- JDS—Java Desktop System
- JFC—Java Foundation Classes
- JFET—Junction Field-Effect Transistor
- JFS—IBM Journaling File System
- JINI—Jini Is Not Initials
- JIT—Just-In-Time
- JME—Java Micro Edition
- JMX—Java Management Extensions
- JMS—Java Message Service
- JNDI—Java Naming and Directory Interface
- JNI—Java Native Interface
- JNZ—Jump non-zero
- JPEG—Joint Photographic Experts Group
- JRE—Java Runtime Environment
- JS—JavaScript
- JSE—Java Standard Edition
- JSON—JavaScript Object Notation
- JSP—Jackson Structured Programming
- JSP—JavaServer Pages
- JTAG—Joint Test Action Group
- JVM—Java Virtual Machine
- K&R—Kernighan and Ritchie
- K8s—Kubernetes
- KB—Keyboard
- Kb—Kilobit
- KB—Kilobyte
- KB—Knowledge Base
- Kbps—Kilobits per second
- KiB—Kibibyte
- KDE—K Desktop Environment
- kHz—Kilohertz
- KRL—Knowledge Representation Language
- KVM—Keyboard, Video, Mouse
- L10N—Localization
- L2TP—Layer two Tunneling Protocol
- LACP—Link Aggregation Control Protocol
- LAMP—Linux Apache MySQL Perl
- LAMP—Linux Apache MySQL PHP
- LAMP—Linux Apache MySQL Python
- LAN—Local Area Network
- LBA—Logical Block Addressing
- LB—Load Balancer
- LCD—Liquid Crystal Display
- LCR—Least Cost Routing
- LCOS—Liquid Crystal On Silicon
- LDAP—Lightweight Directory Access Protocol
- LE—Logical Extents
- LED—Light-Emitting Diode
- LF—Line Feed
- LF—Low Frequency
- LFS—Linux From Scratch
- LGA—Land Grid Array
- LGPL—Lesser General Public License
- LIB—LIBrary
- LIF—Low Insertion Force
- LIFO—Last In First Out
- LILO—Linux Loader
- LIP—Loop Initialization Primitive
- LISP—LISt Processing
- LKML—Linux Kernel Mailing List
- LM—Lan Manager
- LOC—Lines of Code
- LPC—Lars Pensjö C
- LPI—Linux Professional Institute
- LPT— Line Print Terminal
- LRU—Least Recently Used
- LSB—Least Significant Bit
- LSB—Linux Standard Base
- LSI—Large-Scale Integration
- LTE—Long Term Evolution
- LTL—Linear Temporal Logic
- LTR—Left-to-Right
- LUG—Linux User Group
- LUN—Logical Unit Number
- LV—Logical Volume
- LVD—Low Voltage Differential
- LVM—Logical Volume Management
- LZW—Lempel-Ziv-Welch
- NAC—Network Access Control
- NACK—Negative ACKnowledgement
- NAK—Negative AcKnowledge Character
- NaN—Not a Number
- NAP—Network Access Protection
- NAS—Network-Attached Storage
- NASM—Netwide ASseMbler
- NAT—Network Address Translation
- NCP—NetWare Core Protocol
- NCQ—Native Command Queuing
- NCSA—National Center for Supercomputing Applications
- NDIS—Network Driver Interface Specification
- NDPS—Novell Distributed Print Services
- NDS—Novell Directory Services
- NEP—Network Equipment Provider
- NetBIOS—Network Basic Input/Output System
- NetBT—NetBIOS over TCP/IP
- NEXT—Near-End CrossTalk
- NFA—Nondeterministic Finite Automaton
- NFC—Near-field communication
- NFS—Network File System
- NGL—aNGeL
- NGSCB—Next-Generation Secure Computing Base
- NI—National Instruments
- NIC—Network Interface Controller or Network Interface Card
- NIM—No Internal Message
- NIO—Non-blocking I/O
- NIST—National Institute of Standards and Technology
- NLE—Non-Linear Editing system
- NLP—Natural Language Processing
- NLS—Native Language Support
- NMI—Non-Maskable Interrupt
- NNTP—Network News Transfer Protocol
- NOC—Network Operations Center
- NOP—No OPeration
- NOS—Network Operating System
- NP—Nondeterministic Polynomial time
- NPL—Netscape Public License
- NPTL—Native POSIX Thread Library
- NPU—Network Processing Unit
- NS—Netscape
- NSIS—Nullsoft Scriptable Install System
- NSPR—Netscape Portable Runtime
- NSS—Novell Storage Service
- NSS—Network Security Services
- NSS—Name Service Switch
- NT—New Technology
- NTFS—NT Filesystem
- NTLM—NT Lan Manager
- NTP—Network Time Protocol
- NUMA—Non-Uniform Memory Access
- NURBS—Non-Uniform Rational B-Spline
- NVR—Network Video Recorder
- NVRAM—Non-Volatile Random-Access Memory
- OASIS—Organization for the Advancement of Structured Information Standards
- OAT—Operational Acceptance Testing
- OBSAI—Open Base Station Architecture Initiative
- OCR—Optical Character Recognition
- ODBC—Open Database Connectivity
- OEM—Original Equipment Manufacturer
- OES—Open Enterprise Server
- OFDM—Orthogonal Frequency-Division Multiplexing
- OFTC—Open and Free Technology Community
- OID—Object Identifier
- OLAP—Online Analytical Processing
- OLE—Object Linking and Embedding
- OLED—Organic Light Emitting Diode
- OLPC—One Laptop per Child
- OLTP—Online Transaction Processing
- OMF—Object Module Format
- OMG—Object Management Group
- OMR—Optical Mark Reader
- OO—Object-Oriented
- OO—OpenOffice
- OOE—Out-of-Order Execution
- OOM—Out Of Memory
- OOo—OpenOffice.org
- OoOE—Out-of-Order Execution
- OOP—Object-Oriented Programming
- OOTB—Out of the box
- OPML—Outline Processor Markup Language
- ORB—Object Request Broker
- ORM—Object–Relational Mapping
- OS—Open Source
- OS—Operating System
- OSCON—O'Reilly Open Source CONvention
- OSDN—Open Source Development Network
- OSI—Open Source Initiative
- OSI—Open Systems Interconnection
- OSPF—Open Shortest Path First
- OSS—Open Sound System
- OSS—Open-Source Software
- OSS—Operations Support System
- OSTG—Open Source Technology Group
- OTP—One-time password
- OUI—Organizationally Unique Identifier
- P2P—Peer-To-Peer
- PaaS—Platform as a Service
- PAM—Privileged Access Management
- PAN—Personal Area Network
- PAP—Password Authentication Protocol
- PARC—Palo Alto Research Center
- PATA—Parallel ATA
- PBS—Portable Batch System
- PC—Personal Computer
- PCB—Printed Circuit Board
- PCB—Process Control Block
- PC DOS—Personal Computer Disc Operating System
- PCI—Peripheral Component Interconnect
- PCIe—PCI Express
- PCI-X—PCI Extended
- PCL—Printer Command Language
- PCMCIA—Personal Computer Memory Card International Association
- PCM—Pulse-Code Modulation
- PCRE—Perl Compatible Regular Expressions
- PD—Public Domain
- PDA—Personal Digital Assistant
- PDF—Portable Document Format
- PDH—Plesiochronous Digital Hierarchy
- PDP—Programmed Data Processor
- PE—Physical Extents
- PE—Portable Executable
- PERL—Practical Extraction and Reporting Language
- PFA—Please Find Attachment
- PG—Peripheral Gateway
- PGA—Pin Grid Array
- PGA—Programmable Gate Array
- PGO—Profile-Guided Optimization
- PGP—Pretty Good Privacy
- PHP—Hypertext Preprocessor
- PIC—Peripheral Interface Controller
- PIC—Programmable Interrupt Controller
- PID—Proportional-Integral-Derivative
- PID—Process ID
- PIM—Personal Information Manager
- PINE—Program for Internet News and Email
- PING—Packet Internet Gopher
- PIO—Programmed Input/Output
- Pixel—Picture element
- PKCS—Public Key Cryptography Standards
- PKI—Public Key Infrastructure
- PLC—Power Line Communication
- PLC—Programmable Logic Controller
- PLD—Programmable Logic Device
- PL/I—Programming Language One
- PL/M—Programming Language for Microcomputers
- PL/P—Programming Language for Prime
- PLT—Power Line Telecommunications
- PMM—POST Memory Manager
- PNG—Portable Network Graphics
- PnP—Plug-and-Play
- PNRP—Peer Name Resolution Protocol
- PoE—Power over Ethernet
- PoS—Point of Sale
- POCO—Plain Old Class Object
- POID—Persistent Object Identifier
- POJO—Plain Old Java Object
- POP—Point of Presence
- POP3—Post Office Protocol v3
- POSIX—Portable Operating System Interface, formerly IEEE-IX
- POST—Power-On Self Test
- PPC—PowerPC
- PPI—Pixels Per Inch
- PPM—Pages Per Minute
- PPP—Point-to-Point Protocol
- PPPoA—PPP over ATM
- PPPoE—PPP over Ethernet
- PPTP—Point-to-Point Tunneling Protocol
- PR—Pull Request
- PROM—Programmable Read-Only Memory
- PS—PostScript
- PS/2—Personal System/2
- PSA—Professional Services Automation
- PSM—Platform Specific Model
- PSTN—Public Switched Telephone Network
- PSU—Power Supply Unit
- PSVI—Post-Schema-Validation Infoset
- PTS-DOS—PhysTechSoft – Disk Operating System
- PV—Physical Volume
- PVG—Physical Volume Group
- PVR—Personal Video Recorder
- PXE—Preboot Execution Environment
- PXI—PCI eXtensions for Instrumentation
- PRC—Procedure Remote Call
- QDR—Quad Data Rate
- QA—Quality Assurance
- QFP—Quad Flat Package
- QoS—Quality of Service
- QOTD—Quote of the Day
- Qt—Quasar Toolkit[citation needed]
- QTAM—Queued Teleprocessing Access Method
- QSOP—Quarter Small Outline Package
- qWave—Quality Windows Audio/Video Experience
- RACF—Resource Access Control Facility
- RAD—Rapid Application Development
- RADIUS—Remote Authentication Dial In User Service
- RAID—Redundant Array of Independent Disks
- RAII—Resource Acquisition Is Initialization
- RAIT—Redundant Array of Inexpensive Tapes
- RAM—Random-Access Memory
- RARP—Reverse Address Resolution Protocol
- RAS—Reliability, Availability and Serviceability
- RAS—Remote access service
- RC—Region Code
- RC—Release Candidate
- RC—Run Commands
- RCA—Root Cause Analysis
- RCS—Revision Control System
- RD—Remote Desktop
- rd—remove directory
- RDBMS—Relational Database Management System
- RDC—Remote Desktop Connection
- RDF—Resource Description Framework
- RDM—Relational Data Model
- RDOS—Real-time Disk Operating System
- RDP—Remote Desktop Protocol
- RDS—Remote Data Services
- REFAL—Recursive Functions Algorithmic Language
- REP—RAID Error Propagation
- REST—Representational State Transfer
- RESV—Reservation Message
- regex—Regular Expression
- regexp—Regular Expression
- RF—Radio Frequency
- RFC—Request For Comments
- RFI—Radio Frequency Interference
- RFID—Radio Frequency Identification
- RGB—Red, Green, Blue
- RGBA—Red, Green, Blue, Alpha
- RHL—Red Hat Linux
- RHEL—Red Hat Enterprise Linux
- RIA—Rich Internet Application
- RIAA—Recording Industry Association of America
- RIP—Raster Image Processor
- RIP—Routing Information Protocol
- RIR—Regional Internet registry
- RISC—Reduced Instruction Set Computer
- RISC OS—Reduced Instruction Set Computer Operating System
- RJE—Remote Job Entry
- RLE—Run-Length Encoding
- RLL—Run-Length Limited
- rmdir—remove directory
- RMI—Remote Method Invocation
- RMS—Richard Matthew Stallman
- ROM—Read-Only Memory
- ROMB—Read-Out Motherboard
- ROM-DOS—Read-Only Memory – Disk Operating System
- RPA—Robotic Process Automation
- RPC—Remote Procedure Call
- RPG—Report Program Generator
- RPM—RPM Package Manager
- RRAS—Routing and Remote Access Service
- RSA—Rivest Shamir Adleman
- RSI—Repetitive Strain Injury
- RSS—Radio Service Software
- RSS—Rich Site Summary, RDF Site Summary, or Really Simple Syndication
- RSVP—Resource Reservation Protocol
- RTAI—Real-Time Application Interface
- RTC—Real-Time Clock
- RTE—Real-Time Enterprise
- RTEMS—Real-Time Executive for Multiprocessor Systems
- RTF—Rich Text Format
- RTL—Right-to-Left
- RTMP—Real Time Messaging Protocol
- RTOS—Real-Time Operating System
- RTP—Real-time Transport Protocol
- RTS—Ready To Send
- RTSP—Real Time Streaming Protocol
- RTTI—Run-time Type Information
- RTU—Remote Terminal Unit
- RWD—Responsive Web Design
- TAO—Track-At-Once
- TAPI—Telephony Application Programming Interface
- TASM—Turbo ASseMbler
- TB—TeraByte
- Tcl—Tool Command Language
- TCP—Transmission Control Protocol
- TCP/IP—Transmission Control Protocol/Internet Protocol
- TCU—Telecommunication Control Unit
- TDMA—Time-Division Multiple Access
- TDP—Thermal Design Power
- TFT—Thin-Film Transistor
- TFTP—Trivial File Transfer Protocol
- TI—Texas Instruments
- TIFF—Tagged Image File Format
- TLA—Three-Letter Acronym
- TLD—Top-Level Domain
- TLS—Thread-Local Storage
- TLS—Transport Layer Security
- TLV—Type—length—value
- tmp—temporary
- TNC—Terminal Node Controller
- TNC—Threaded Neill-Concelman connector
- TPF—Transaction Processing Facility
- TPM—Trusted Platform Module
- TROFF—Trace Off
- TRON—Trace On
- TRON—The Real-time Operating system Nucleus
- TRSDOS—Tandy Radio Shack – Disk Operating System
- TSO—Time Sharing Option
- TSP—Traveling Salesman Problem
- TSR—Terminate and Stay Resident
- TTA—True Tap Audio
- TTF—TrueType Font
- TTL—Transistor—Transistor Logic
- TTL—Time To Live
- TTS—Text-to-Speech
- TTY—Teletype
- TUCOWS—The Ultimate Collection of Winsock Software
- TUG—TeX Users Group
- TWAIN—Technology Without An Interesting Name
- UAAG—User Agent Accessibility Guidelines
- UAC—User Account Control
- UART—Universal Asynchronous Receiver/Transmitter
- UAT—User Acceptance Testing
- UB—Undefined Behavior
- UCS—Universal Character Set
- UDDI—Universal Description, Discovery, and Integration
- UDMA—Ultra DMA
- UDP—User Datagram Protocol
- UEFI—Unified Extensible Firmware Interface
- UHF—Ultra High Frequency
- UI—User Interface
- UL—Upload
- ULA—Uncommitted Logic Array
- ULSI—Ultra Large Scale Integration
- UMA—Upper Memory Area
- UMB—Upper Memory Block
- UML—Unified Modeling Language
- UML—User-Mode Linux
- UMPC—Ultra-Mobile Personal Computer
- UMTS—Universal Mobile Telecommunications System
- UNC—Universal Naming Convention
- UNIVAC—Universal Automatic Computer (By MKS)
- UPS—Uninterruptible Power Supply or Uninterrupted Power Supply
- URI—Uniform Resource Identifier
- URL—Uniform Resource Locator
- URN—Uniform Resource Name
- USB—Universal Serial Bus
- usr—User System Resources
- USR—U.S. Robotics
- UTC—Coordinated Universal Time
- UTF—Unicode Transformation Format
- UTP—Unshielded Twisted Pair
- UTRAN—Universal Terrestrial Radio Access Network
- UUCP—Unix to Unix Copy
- UUID—Universally Unique Identifier
- UUN—Universal User Name
- UVC—Universal Virtual Computer
- UWP—Universal Windows Platform
- UX—User Experience
- var—variable
- VoLTE—Voice Over Long Term Evolution
- VAX—Virtual Address eXtension
- VCPI—Virtual Control Program Interface
- VB—Visual Basic
- VBA—Visual Basic for Applications
- VBS—Visual Basic Script
- VDI—Virtual Desktop Infrastructure
- VDU—Visual Display Unit
- VDM—Virtual DOS machine
- VDSL—Very High Bitrate Digital Subscriber Line
- VESA—Video Electronics Standards Association
- VFAT—Virtual FAT
- VHD—Virtual Hard Disk
- VFS—Virtual File System
- VG—Volume Group
- VGA—Video Graphics Array
- VHF—Very High Frequency
- VIRUS—Vital Information Resource Under Seize
- VLAN—Virtual Local Area Network
- VLSM—Variable-length subnet masking
- VLB—Vesa Local Bus
- VLF—Very Low Frequency
- VLIW—Very Long Instruction Word
- VLSI—Very-Large-Scale Integration
- VM—Virtual Machine
- VM—Virtual Memory
- VMM—Virtual Machine Monitor
- VNC—Virtual Network Computing
- VOD—Video On Demand
- VoIP—Voice over Internet Protocol
- VPN—Virtual Private Network
- VPS—Virtual Private Server
- VPU—Visual Processing Unit
- VR—Virtual Reality
- VRML—Virtual Reality Modeling Language
- VSAM—Virtual Storage-Access Method
- VSAT—Very Small Aperture Terminal
- VT—Video Terminal
- VTL—Virtual Tape Library
- VTAM—Virtual Telecommunications Access Method
- VRAM—Video Random-Access Memory
- W3C—World Wide Web Consortium
- WWDC—Apple World Wide Developer Conference
- WAFS—Wide Area File Services
- WAI—Web Accessibility Initiative
- WAIS—Wide Area Information Server
- WAN—Wide Area Network
- WAP—Wireless Access Point
- WAP—Wireless Application Protocol
- WASM—Watcom ASseMbler
- WBEM—Web-Based Enterprise Management
- WCAG—Web Content Accessibility Guidelines
- WCF—Windows Communication Foundation
- WDM—Wavelength-Division Multiplexing
- WebDAV—WWW Distributed Authoring and Versioning
- WEP—Wired Equivalent Privacy
- WFI—Wait For Interrupt
- WiMAX—Worldwide Interoperability for Microwave Access
- WinFS—Windows Future Storage
- WinRT—Windows RunTime
- WINS—Windows Internet Name Service
- WLAN—Wireless Local Area Network
- WMA—Windows Media Audio
- WMI—Windows Management Instrumentation
- WMV—Windows Media Video
- WNS—Windows Push Notification Service
- WOL—Wake-on-LAN
- WOR—Wake-on-Ring
- WORA—Write once, run anywhere
- WORE—Write once, run everywhere
- WORM—Write Once Read Many
- WPA—Wi-Fi Protected Access
- WPAD—Web Proxy Autodiscovery Protocol
- WPAN—Wireless Personal Area Network
- WPF—Windows Presentation Foundation
- WS-D—Web Services-Discovery
- WSDL—Web Services Description Language
- WSFL—Web Services Flow Language
- WUSB—Wireless Universal Serial Bus
- WWAN—Wireless Wide Area Network
- WWID—World Wide Identifier
- WWN—World Wide Name
- WWW—World Wide Web
- WYSIWYG—What You See Is What You Get
- WZC—Wireless Zero Configuration
- XAML—eXtensible Application Markup Language
- XDM—X Window Display Manager
- XDMCP—X Display Manager Control Protocol
- XCBL—XML Common Business Library
- XHTML—eXtensible Hypertext Markup Language
- XILP—X Interactive ListProc
- XML—eXtensible Markup Language
- XMMS—X Multimedia System
- XMPP—eXtensible Messaging and Presence Protocol
- XMS—Extended Memory Specification
- XNS—Xerox Network Systems
- XP—Cross-Platform
- XP—Extreme Programming
- XPCOM—Cross Platform Component Object Model
- XPI—XPInstall
- XPIDL—Cross-Platform IDL
- XPS—XML Paper Specification
- XSD—XML Schema Definition
- XSL—eXtensible Stylesheet Language
- XSL-FO—eXtensible Stylesheet Language Formatting Objects
- XSLT—eXtensible Stylesheet Language Transformations
- XSS—Cross-Site Scripting
- XTF—eXtensible Tag Framework
- XTF—eXtended Triton Format
- XUL—XML User Interface Language
- XVGA—Extended Video Graphics Adapter
- Y2K—Year Two Thousand
- Y2K38—Year Two Thousand Thirty Eight
- YAAF—Yet Another Application Framework
- YACC—Yet Another Compiler Compiler
- YAGNI—You Aren't Gonna Need It
- YAML—YAML Ain't Markup Language
- YARN—Yet Another Resource Negotiator
- YaST—Yet another Setup Tool
- ZCAV—Zone Constant Angular Velocity
- ZCS—Zero Code Suppression
- ZIF—Zero Insertion Force
- ZIFS—Zero Insertion Force Socket
- ZIP—ZIP file archive
- ZISC—Zero Instruction Set Computer
- ZOI—Zero One Infinity
- ZOPE—Z Object Publishing Environment
- ZMA—Zone Multicast Address
- ZPL—Z-level Programming Language