List of file formats beginning with U

• .UAX - Unreal Audio file
• .UB - Audio file (unsigned byte)
• .UC2 - Compressed file archive created by UltraCompressor II (uc2.zip)
• .UCN - New compressed file archive created by UltraCompressor II
• .UCS - Universal Classification Standard Database file
• .UDC - Acrobat Spelling file
• .UDF - Filter (Photostyler)
• .UDL - MS Data Link
• .UDS - Sierra Generations Family file
• .UE2 - Encrypted file archive created by UltraCompressor II
• .UFO - Ulead Object file - Buy Ulead Multimedia Software now!
• .UHA - UHARC Compressed Archive
• .UHS - Universal Hint System (binary file)
• .UI - Espire source code file (Geoworks UI Compiler); User interface (Sprint)
• .UIF - Long prompts for windows (WordPerfect for Win)
• .UIH - Espire header file (Geoworks UI Compiler)
• .UL - Ulaw audio file
• .ULD - Information about uploaded files (Procomm Plus)
• .ULT - Music (UltraTracker)
• .UMB - Backup file (MemMaker)
• .UMX - Unreal music file
• .UNI - Unimod music module (MIKMOD); Datafile (Forecast Pro)
• .UNQ - Fax View file
• .UNX - Text file containing UNIX specific info
• .UPD - Program update infoUpdate data (dBASE)
• .UPO - Compiled update data (dBASE)
• .UPX - ULead Photo Express Saved Image file

• .USB - D-Link FM Radio Update; USB Protocol Analyzer Trace
• .USP - Printer font with USASCII extended character set (PageMaker)
• .USR - User database file (Procomm Plus - Turbo C++ tour)
• .UTF - AOL Updating Files
• .UTL - Sound file
• .UTX - Unreal Texture fileUnicode file
• .UU - Compressed ASCII file archive created by UUDE/ENCODE
• .UUE - Compressed ASCII file archive created by UUENCODE (uuexe515.exe)
• .UVR - Ulead Cool 360 Viewer file - Buy Ulead Multimedia Software now!
• .UW - Audio file (unsigned word)
• .UWL - WordPerfect User word list