Multi-language interface
This application provides for a "multi-language interface"; that is, an interface in which some things can display in one language, while other things display in a different language. In this application, that typically means that the user interface, dialog boxes, windows, and so on, can display in one language. At the same time, system messages can be set to display in another language. And finally, the online help can be set to display in yet a third language.
Granted, most of the time, administrators and users would not want to do this, but it can be helpful to know that you can, should the need arise.
It is also worth mentioning that most language settings can be made—and overridden—at various levels, both system-wide and user-level.
This all starts in the language resource definitions, which are created and maintained using the Language IDs form. That is where language settings for a particular language (culture code combination) are defined and maintained.