Resource file used by the Multilingual User Interface component of Windows 2000 and later; contains resources that allow the Windows interface to be changed to different languages.
Many MUI files can be found within the Windows %SystemRoot%\ directory (e.g., %SystemRoot%\en-US\ in Windows 7). They may also be located within specific program installations, such as Windows Journal, Windows Defender, Windows Mail, and other Microsoft Windows programs, including Notepad (notepad.exe.mui).
Additional language packs can be installed in Windows 7 by selecting Control Panel → Clock, Language, and Region → Change display language → Keyboards and Languages and clicking the Install/uninstall languages... button.
Instrument file used by Myriad musical notation software products such as Harmony Assistant; stores instrument sounds and can be for piano, strings, woodwinds, brass, or a variety of other instruments; used for generating realistic sounds.