| Abbreviation |
Definition |
| U/U |
Unlimited User |
| UART |
Universal Asynchronous Receive Transmitter |
| UDMA |
Ultra ATA/EIDE/UDMA |
| UFC |
Universal Feature Card |
| UFMT |
Unformatted |
| UK |
Ukranian |
| UM |
Under Monitor (Surge Protection) |
| UNATT |
Unattended |
| UNI |
Universal Ports (Parallel or Serial) |
| UNIV |
Universal |
| UNIVTRAY |
Universal Tray |
| UNIX |
UNIX Operating System |
| UNIXCONS |
UNIX Console |
| UNLTD |
Unlimited |
| UNMGD |
Unmanaged |
| UNMGMT |
Unmanagement |
| UPG |
Upgrade |
| UPGKIT |
Upgrade Kit |
| UPS |
Uninterruptable Power Supply |
| USB |
Universal Serial Bus |
| USCSI |
Ultra SCSI |
| USP |
Upgrade Subscription Plan |
| UTIL |
Utility |
| UTP |
Unshielded Twisted Pair |
| UWSCSI |
Ultra Wide SCSI |
| U2WSCSI |
Ultra 2 Wide SCSI |