UART - Universal Asynchronous Receiver-Trnsmitter (Receptor Transmisor Asincrono Universal).

UDP - User Datagram Protocol.

UDT - Uniform Data Transfer (Transferencia de Datos Uniforme).

UMA - Upper Memory Area (área superior de memoria).

UMB - Upper Memory Block (Bloque Superior de Memoria).

UPP - Universal Plug and Play.

URL - Uniform Resource Locator.

USB - Universal Serial Bus

USRT - Universal Synchronous Receiver-Transmitter (receptor-transmisor universal síncrono).

UTP - Unshielded Twisted Pair (par coaxial no apantallado).

UUCP - Unix -to- Unix Copy.