U
UAA (Universally Administred Address)
UAA (Universal Audio Architecture)
UART (Universal Asynchronous Receiver/Transmitter)
UDF (Universal Disk Format)
UDG-PI (Unix Developer Guide - Programming Interface)
UDO (Ultra Density Optical)
UDP/IP (User Datagram Protocol/Internet Protocol)
UEP (Unequal Error Protection)
UFS (Unix File System)
Ugello
ULSI (Ultra Large Scale Integration)
Ultimo miglio
Ultra ATA/33
Ultra ATA/66
Ultra DMA/33
Ultra DMA/66
Ultra MicroDot
Ultra Sparc IV
Ultra Wide SCSI
Ultra/150 CQ (Ultra/150 Command Queuing)
Ultra160 SCSI
Ultra2 SCSI
Ultra3 SCSI
Ultra320 SCSI
Ultra4 SCSI
Ultra5 SCSI
Ultrapassword
Ultrashadow
ULV (Ultra Low Voltage)
UMA (Upper Memory Area)
UMB (Upper Memory Block)
UMTS (Universal Mobile Telecommunications System)
Unbunding
Underflow
Undo
Unicast
Unità di memoria di massa
Unix (Uniplexed Information and Computing System)
Unix 95
UnixWare
Untrusted
UOK? (Are You OK?)
Upgrade
Upload
UPnP (Universal Plug aNd Play)
UPS (Uninterruptible Power Supply)
Upstream
URL (Uniform Resource Locator)
USB (Universal Serial Bus)
USB 1
USB 2
USB Hub
USB OTG (USB On The Go)
U-SCSI/W-SCSI (UltraSCSI, WideSCSI)
USENET
User agent
User-friendly
User-id
Username
Usr
UTDP (Ultra Threaded Dispatch Processor)
Utility
UTP (Unshielded Twisted Pair)
UUCP (Unix-to-Unix Copy)
UUencode / UUdecode
UV (Ultra-Violet)
UWB (Ultra Wide Band)

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