| Abbreviation | Definition |
|---|---|
| UCR | User Change Request |
| UCSS | Unified Communications Software Subscription |
| UCX | Universal Component eXtensions |
| UDA | USB Debug Adapter |
| UDAPL | User Direct Access Programming Library |
| UDC | User Defined Change |
| UDE | Universal Debug Engine |
| UDE | UnrealScript Development Environment |
| UDFs | User-Defined Functions |
| UDI | Uniform Driver Interface |
| UDI | Unrestricted Digital Information |
| UDIG | User-friendly Desktop Internet GIS |
| UDK | UnixWare/OpenServer Development Kit |
| UDLS | Universal Driver Library Software |
| UDO | User Defined Object |
| UDP | Unreliable Damn Protocol |
| UDR | User Data report |
| UDS | Universal Data Server |
| UDSS | User Defined Software Stacks |
| UED | User Environment Design |