Multilingual User Interface (MUI) is the name of a Microsoft technology for Microsoft Windows, Microsoft Office and other applications that allows for the installation of multiple interface languages on a single system. On a system with MUI, each user would be able to select his or her own preferred display language.
Up to Windows XP, MUI packs for a product are applied on top of an English version to provide a localized user experience. Windows Vista further advances MUI technology with support for single, language-neutral, language-independent binary files supporting multiple language skins, with the language-specific resources contained in separate binaries. The MUI architecture separates the language resources for the user interface from the binary code of the operating system. This separation makes it possible to change languages completely without changing the core binaries of Windows Vista, or to have multiple languages installed on the same computer with the same core binaries being used. Languages are applied as language packs containing the resources required to localize part of, or the entire, user interface in Windows Vista.
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