| Nom | Description |
| U NII | Unlicensed National Information Infrastructure |
| U/L | Universal / Local |
| UA |
| Universal Access |
| Unnumbered Acknowledgement |
| Unnumbered Acknowledgment |
| User Account |
| User Agent |
| User Area |
| UAA | UnternehmensAnwendungsArchitektur |
| UAB | UNIX AppleTalk Bridge |
| UAC |
| Universal Access Control |
| Urban Area Coverage |
| UADPS | Uniform Automatic Data Processing System |
| UADS | User Attribute Data Set |
| UAE |
| Unknown / Unrecoverable Application Error |
| Unrecoverable Application Error |
| User Agent Entity |
| UAF | User Authorization File |
| UAL |
| Unite Arithmetique et Logique |
| User Agent Layer |
| UAM | User Authentication Method |
| UAOS | User Alliance for Open Systems |
| UAPDU | User Agent Protocol Data Unit |
| UART |
| Universal Asynchronous Receive and Transmit |
| Universal Asynchronous Receiver Transmitter |
| Universal Asynchronous Receiver/Transmitter |
| UAS |
| UnAvailable Second |
| UnAvailable Seconds |
| UASFE | UnAvailable Second, Far End |
| UASL | User Agent SubLayer |
| UAV |
| Unmanned Aerial Vehicle |
| Unmanned Aerospace Vehicle |
| Unmanned Air Vehicle |
| Unmanned Airborne Vehicle |
| UAWG | Universal ADSL Working Group |
| UBA | UniBus Adapter |
| UBC | University of British Columbia ( Vancouver, Canada ) |
| UBCIM | Universal Bibliographic Control / International MARC |
| UBD | User Brain Damage |
| UBE | Unsolicited Bulk Email spam, Internet |
| UBHR | User Block Handling Routine |
| UBI | Universalité Bidirectionnalité Interactivité |
| UBNI | Ungermann Bass Network Interface |
| UBR |
| Unspecified Bit Rate |
| Unspecified Bit Rate ( ATM ) |
| UBS | Unit Backspace Character |
| UBT | Universal Bus Transceiver |
| UC2 | Compressed File "file name extension" "UltraCompressor" |
| UCA2 | Utility Communications Architecture version 2 ( IEEE standard ) |
| UCAID | University Corporation for Advanced Internet Development |
| UCAV | Uninhabited Combat Aerial Vehicle |
| UCC |
| Uniform Code Council |
| Uniform Commercial Codes |
| Unité de Commande et de Contrôle |
| Universal Commercial Code |
| UCCE | University Consortium for Continuing Education |
| UCD |
| Uniform Call Distribution |
| Upstream Channel Description |
| UCE |
| Union Carbide Electronics |
| Unsolicited Commercial E mail Usenet, spam |
| Unsolicited Commercial Email |
| UCF | Underground Computing Foundation |
| UCI | User Computer Interface |
| UCL |
| Universal Communications Language |
| University College, London |
| UCLA |
| University of California at Los Angeles |
| University of California, Los Angeles |
| UCP | Universal Computer Protocol SMS, Europe |
| UCR | Under Color Removal |
| UCS |
| Unicode Conversion Support |
| Uniform Communication Standard |
| Universal Character Set |
| Universal Classification System |
| Universal Component System |
| Universal [multiple octet] coded Character Set |
| User Coordinate System |
| UCSB | University of California at Santa Barbara org. USA |
| UCSD |
| University California San Diego |
| University of California, San Diego |
| UCT | Universal Coordinated Time |
| UCW | Unit Control Word |
| UD DVD | Ultra Definition Digital Video Disk |
| UD | Unit Data |
| UDA |
| Universal Data Access |
| User-Defined Applications |
| UDB |
| Unified Database |
| Universal Data Base |
| Universal Database Server |
| UDC |
| Universal Decimal Classification |
| Universal Digit Channel |
| Universal Display Corporation ( Bala Cynwyd PA ) |
| Update Center |
| User Defined Command |
| User Defined Commands |
| UDCP | USSD Dialogue Control Protocol ( GSM ) |
| UDD | User Data Document |
| UDDI | Universal Description Discovery and Integration |
| UDE | Universal Data Exchange |
| UDEC | Universal Digital Electronic Computer |
| UDF |
| Universal Disc Format |
| Universal Disk Format |
| User Definable Font |
| User Defined Function |
| User Defined Functions |
| UDG | User Defined Gateway |
| UDI | Universal Development Interface |
| UDK |
| UmweltDatenKatalog |
| User Define Key |
| UDL | Uniformly Distributed Load |
| UDLC | Universal Data Link Control |
| UDLI | ??? [hardware desription language] "HDL", "UDL/I" |
| UDMA | Ultra Direct Memory Access |
| UDP |
| Usenet Death Penalty Usenet, spam |
| User Datagram Protocol |
| User Datagram Protocol [ A TCP complement that offers a connectionless datagram service that guarantees neither delivery nor correct sequencing of delivered packets (much like IP) ] |
| User Death Penalty |
| UDPIP | User Datagram Protocol / Internet Protocol, "UDP/IP" |
| UDS | Universal Data Set |
| UDT |
| Uniform Data Transfer |
| User Defined Type |
| User defined DataType |
| UDVM | Universal Data Voice Multiplexer |
| UDWDM | Ultra Dense Wavelength Division Multiplexing [ 1022 channels of 37 Mbits/s on a single fiber, 37 Gbits/s network demonstrated by researchers from Bell Labs ] |
| UE | User Element |
| UEC | User Environment Component |
| UEIDE | Ultra Enhanced Integrated Drive Electronics |
| UEL | Upper Explosive Limit |
| UES | User Electronic Signature |
| UEV | User End of Volume |
| UFD | User Friendly Diagnostics |
| UFO | Unidentified Flying Object |
| UFP | Utility Facilities Program |
| UFPT | Ultra Fine Pitch Technology |
| UFS |
| Ultra Fast Switching |
| Universal File System |
| Unix File System |
| UFST | Universal Font Scaling Technology |
| UG | User Group |
| UGAP | Union des Groupements d'Achat Public |
| UHC | United Hitech Corporation manufacturer, Taiwan |
| UHCI | Universal Host Controller Interface |
| UHD | Ultra High Density |
| UHF |
| Ultra - High Frequency |
| Ultra High Frequency |
| Ultra High Frequency ( 300MHz 3GHz ) |
| UHL |
| Universal Hypertext Link |
| User Head Label |
| User Header Label |
| UHLL | Ultrahigh Level Language |
| UHQ |
| Ultra High Quality |
| Ultra High Quality (image technology) |
| UHR | Ultra High Resolution (Radar) |
| UHS | Ultra High Speed |
| UHV/CVD | Ultra High Vacuum Chemical Vapor Deposition |
| UHV | UltraHigh Vacuum |
| UI |
| UNIX International |
| Unit Interval |
| Unit Interval ( SCSI ) |
| Unix International manufacturer, Unix |
| Unnumbered Information |
| Unnumbered Interrupt |
| User Interface |
| UIC | User Identification Code |
| UID |
| Unit IDentifier cryptography, EES |
| Universal Individual Identifier |
| User IDentification |
| User Identifier |
| UIDE | User Interface Design Environment |
| UIDL | Unique ID Listing |
| UIF | USB Interface Firmware |
| UIFN | Universal International Freephone Number |
| UIL |
| Univac Interactive Language |
| User Interface Language |
| UIMS |
| User Interface Management System |
| User Interface Management Systems |
| UIO | Universal InterOperability |
| UIOC | Universal I/O Controller |
| UIS |
| UmweltInformationsSystem |
| Unclamped Inductive Switching |
| Universal Information Services |
| UISRM | User Interface System Reference Model |
| UIST | User Interface Software and Technology (symposium) |
| UIT R | Union Internationale des Telecommunications Radiocommunications |
| UIT T | Union Internationale des Telecommunications Telecommunications |
| UIT | Union Internationale des Telecommunications |
| UITP | Universal Information Transport Plan |
| UJT | UniJunction Transistor |
| UK | United Kingdom |
| UKERNA | United Kingdom Education and Research Networking Association |
| UKRA | United Kingdom Registration Authority |
| UL |
| Underwriters Laboratories |
| Underwriters' Laboratories |
| Unit Load |
| Unordered List |
| Upload |
| Urban Legend |
| User Location |
| ULA |
| Uncommitted Logic Array |
| Upper Layer Architecture |
| ULANA | Unified Local Area Network Architecture |
| ULC |
| Underwriters' Laboratories of Canada |
| Universal Logic Circuit |
| ULCC |
| University of London Computer Center |
| University of London Computing Centre |
| ULCT | Upper Layer Conformance Testing |
| ULI | Upper Level Interface ( ASAM ) |
| ULIX | Serveur Internet |
| ULN | Universal Link Negotiation |
| ULP |
| Upper Layer Protocol / Upper Layer Process |
| Upper Layer Protocols |
| Upper Level Protocol |
| ULPI | Unit Level Prototype Implementaion |
| ULPM | Universal Linear Power Module |
| ULS | Unknown Line State |
| ULSI | Ultra Large Scale Integration |
| ULTRA | Underground Legion of Terroristic Research Activists |
| UMA |
| Unified Memory Architecture |
| Universal Measurement Architecture |
| Upper Memory Area |
| UMADS | Universal Measurement Architecture Data Storage |
| UMB | Upper Memory Block |
| UMC |
| United Microelectronics Corporation ( Taiwan ) |
| United Microelectronics Corporation manufacturer |
| UMD | User Manager for Domains |
| UME | UNI Management Entity |
| UML |
| Unified Method Language |
| Unified Modeling Language |
| Unified Modeling Language ( OO ) |
| Unified Modelling Language |
| Universal Modeling Language |
| UMPDU | User Message Protocol Data Unit |
| UMS |
| Unified Messaging Server |
| User Mode Scheduler |
| UMTF | Unix Migration Task Force |
| UMTS |
| Universal Mobile Telecom Services |
| Universal Mobile Telecommunication System |
| Universal Mobile Telecommunications System |
| UN | United Nations |
| UNA |
| Universal Network Architecture |
| Upstream Neighbors Address |
| UNARP | UNsolicited Address Resolution Protocol |
| UNC |
| Unified Coarse ( thread ) |
| Uniform Naming Convention / Universal Naming Convention |
| Universal Naming Convention |
| University of North Carolina ( at Chapel Hill, www.unc.edu ) |
| Uuencoded Netnews Collator |
| UNCID |
| UNiform rules of Conduct for Interchange of Trade data by teletransmission"EDIFACT" |
| Uniform rules of Conduct for Interchange of trade Data by teletransmission |
| UNCLE | Unix Net for Computer security in Law Enforcement |
| UNCOL | Universal Computed Oriented Language |
| UNEDIFACT | United Nations EDIFACT "ISO 9735, EDIFACT", "UN/EDIFACT" |
| UNESCO | United Nations Educational Scientific and Cultural Organization |
| UNF | Unified Fine ( thread ) |
| UNGTDI | United Nations Guidelines for Trade Data Interchange UN/EDIFACT,predecessor, "UN/GTDI" |
| UNH IOL | University of New Hampshire InterOperability Laboratory |
| UNHIOL | University of New Hampshire InterOperability Lab |
| UNI |
| Universal Network Interface |
| User Network Interface |
| User-to-Network Interface (ATM specification) |
| UNICODE |
| "extension to 24 bits of the ASCII characters set" |
| Unique, Universal, and Uniform character enCoding |
| UNICOM | Universal Integrated Communication |
| UNICOS | Universal Compiler FORTRAN compatible |
| UNII | Unlicensed National Information Infrastructure |
| UNISTAR | UNIversal Single call Telecommunications Answering and Repair |
| UNIVAC | UNIVersal Automatic Computer |
| UNIX | "AT&T Bell Laboratories Operating System" |
| UNJEDI | United Nations Joint Electronic Data Interchange |
| UNM | University of New Mexico ( Albuquerque NM ) |
| UNMA | Unified Network Management Architecture |
| UNS | Unified Special ( thread ) |
| UNSM |
| United Nations Standard Message, |
| United Nations Standard Messages |
| UNSPSC | Universal Standard Products and Services Classification |
| UNTDED | United Nations Trade Data Elements Directory |
| UNTDI | United Nations Trade Data Interchange |
| UNTDID | United Nations Trade Data Interchange Directory |
| UOF | Unusual Order Form |
| UP |
| Uni Processor [system] |
| Uni-Processor |
| Uniprocessor |
| UPAM | User Primary Access Method |
| UPC |
| Universal Product Code |
| Universal Product/Program Code |
| Update Protect Checking |
| Usage Parameter Control |
| User Parameter Control |
| Utility Port Conditioner |
| UPG | Upgrade |
| UPH | Units Per Hour |
| UPI |
| United Phreaker's Incorporated |
| United Press International |
| UPL | User Program Language |
| UPM |
| Umdrehungen Pro Minute |
| Unix Programmer's Manual |
| User Profile Management |
| UPN |
| Umgekehrte Polnische Notation |
| Universal Product Number |
| UPP |
| Universal Payment Preamble |
| Universal Procedure Pointer |
| UPPS | Universal Portable Protocol Stack / Support |
| UPROM | Unerasable Programmable Read Only Memory |
| UPS |
| Uninterruptible Power Supply |
| Uninterruptible Power Supply/System |
| Uninterruptible Power System |
| United Parcel Service |
| Unix Print Services |
| UPT |
| Universal Personal Telecommunication |
| Universal Personal Telecommunications |
| Universelle Personengebundene Telekommunikation |
| UPU | Universal Postal Union |
| URA | Uniform Resource Agent |
| URAN | Universally Reconstructable Artificial Neural ( network ) |
| URB | Universal Request Broker |
| URBAN | Undaground Rap Blastin Asiatic Newsletter |
| URC |
| Uniform Resource Characteristics |
| Uniform Resource Citation |
| Uniform Resources Characteristics |
| Unit Record Controller |
| UREC | Unité Réseau du CNRS |
| UREP | Unix RSCS Emulation Protocol |
| URG | Urgent (flag) |
| URI |
| Uniform Resource Identifier |
| University Research Initiative |
| URL |
| Uniform Resource Locator |
| Uniform Resource Locator / Universal Resource Locator |
| Universal Resource Locator |
| URN |
| Uniform Resource Name |
| Uniform Resource Name/Number |
| URP | Unit Record Processor |
| URRP | University Resident Research Program |
| URSI | Union Radio Scientifique Internationale |
| URSN | Unique Resource Serial Number |
| URSSAF | Union de Recouvrement des cotisations de Sécurité Sociale et d'Allocations Familiales |
| US |
| Unit Separator |
| Unit Separator ( ASCII control code ) |
| Unit Separator (ASCII) |
| United States |
| USA |
| Undedicated Switch Access |
| United Software Association |
| United States of America |
| USAC | United States Auto Club |
| USACNII | US Advisory Council on the National Information Infrastructure |
| USAF | United States Air Force |
| USAFA | United States Air Force Academy |
| USAFE | United States Air Forces in Europe |
| USART |
| Universal Synchronous Asynchronous Receiver / Transmitter |
| Universal Synchronous Asynchronous Receiver/Transmitter |
| Universal Synchronous/Asynchronous Receiver/Transmitter |
| USASI | United States of America Standards Institute |
| USB |
| Universal Serial Bus |
| Upper SideBand |
| USBPG | Universal Serial Bus Promoter Group |
| USC | User Steering Committee |
| USCAR | United States Council for Automotive Research |
| USCIC | U.S. Country Information Center |
| USCP | Unicos Station Call Processor [protocol] |
| USD | User's Supplementary Documents |
| USDC |
| United States Display Consortium |
| Universal Switched Data Capability |
| USDN | United States Digital Network |
| USEC | User based SECurity [model] |
| USENET |
| USErs' NETwork |
| User's Network |
| USERID | User Identification |
| USFDC | U.S. Financial Data Center |
| USFO | United States Field Operations |
| USG | Unix Support Group |
| USIBC | U.S. Integrated Business Center |
| USIC | User Specific Integrated Circuit |
| USIPA | United States Internet Providers Association |
| USITA | United States Independent Telephone Association |
| USL |
| Unix System Laboratories |
| Unix Systems Laboratories |
| USM |
| UnSharp Masking |
| Unsharped Masking |
| USMA | United States Military Academy |
| USMP | U.S. Manufacturing Planning |
| USMTF | United States Message Text Format |
| USNA | United States Naval Academy |
| USNC | United States National Committee |
| USO | Universal Service Order |
| USOC |
| Universal Service Ordering Code |
| Universal Service Ordering Codes |
| USP |
| Universal Sampling Plan |
| User Stack Pointer |
| USPL | U.S. Price List |
| USPS |
| United States Postal Service |
| United States Postal Services |
| USPTO | United States Patent and Trademark Office |
| USQ | Unsqueezed |
| USR |
| U.S. Robotics manufacturer |
| US Robotics |
| USRobotics |
| User Service Routines |
| USRA | Universities Space Research Association |
| USRN | Unité de Synchronisation du Réseau Numérique |
| USRT |
| Universal Synchronous Receiver Transmitter |
| Universal Synchronous Receiver/Transmitter |
| USS |
| (VTAM) Unformatted Systems Service |
| Unformatted System Services |
| User Support System |
| USSA | User Supported Software Association |
| USSD | Unstructured Supplementary Service Data ( GSM ) |
| USSOCOM | United States Special Operation Command |
| USSPACECOM | United States Space Command |
| USSS | United States Secret Service |
| USTA | United States Telephone Association |
| USTR | United States Trade Representative |
| USV |
| Unterbrechungsfreie Strom Versorgung |
| Unterbrechungsfreie StromVersorgung |
| User Services |
| USWC | Uncached Speculative Write Combining |
| UT |
| Universal Time |
| Universal Time [+0000] |
| Upper Tester |
| User Terminal |
| Utah |
| UTAM | Unlicensed Transition And Management |
| UTC |
| Coordinated Universal Time |
| Coordinated Universal Time / Temps Universel Coordonné (not actually an acronym) |
| Universal Time Coordinated |
| Universal Time Coordinates |
| Universal Time Coordinates [+0000] |
| UTE | Union Technique de l'Electricité |
| UTF | Unicode Transformation Format |
| UTI |
| Universal Test Interface |
| Universal Text Interchange |
| Universal Text Interchange/Interface |
| Universal Transducer Interface |
| UTL | User Trailer Label |
| UTLB | Unified Translation Look aside Buffer |
| UTM |
| Ultra Thin Multilayer ( board ) |
| Universal Transaction Monitor |
| Universeller TransaktionsMonitor |
| UTMS | User Total Management System |
| UTOPIA |
| Universal Test & Operations Physical layer Interface for ATM |
| Universal Test and Operations PHY Interface for ATM |
| Universal Test and Operations Physical layer Interface to ATM |
| UTP |
| Unshielded Twisted Pair |
| Unshielded Twisted Pair [cable] |
| Unshielded Twisted-Pair |
| UTQFP | Ultra Thin Quad Flat Pack |
| UTRA | Universal Terrestrial Radio Access |
| UTS |
| Unbound Task Set |
| Universal Time share System |
| Universal Timesharing System |
| UTSL | Use the Source Luke |
| UTTC | Universal Tape To Tape Converter |
| UTTP | Unshielded Telephone Twisted Pair |
| UU |
| UUencode |
| Uuencode/Uudecode |
| UUA | Univac Users Association |
| UUCICO | Unix to Unix Copy Incoming Copy Outgoing |
| UUCIO | Unix to Unix Copy In copy Out |
| UUCP |
| Unix To Unix Copy Program |
| Unix to Unix Communication Protocol |
| Unix to Unix Copy Protocol |
| Unix-to-Unix Copy |
| UUD |
| UUDecode |
| UUDecoding |
| Unit Under Development |
| UUDECODE | Unix To Unix Decoding |
| UUE | UUEncoding |
| UUENCODE | Unix To Unix Encoding |
| UUG | Unix User Group |
| UUI | User To User Information |
| UUID | Universal Unique IDentifier |
| UUNET | Unix to Unix NETwork |
| UUS | User to User Signaling Service |
| UUT | Unit Under Test |
| UV | Ultraviolet |
| UVC | Universal Voice Channel |
| UVL | User Volume Label |
| UVLO | UnderVoltage LockOut |
| UVROM | Ultra Violet Read Only Memory |
| UW | Ultra Wide [SCSI] |
| UWR | Ultra Wideband Radio |
| UXGA | Ultra XGA ( 1600 by 1200 pixels ) |
| UXU | Underground Experts United |
