What is a language group?

A language group is a set of all the keyboard layouts, IMEs, fonts (TrueType or bitmap), font links, language packs (LPKs) and codepage translation tables needed by the system to support the given group of languages. The list of installed language groups controls which input and system locales can be selected.

Installation of a language group copies (but does not activate) the necessary keyboard files, Input Method Editors (IMEs), TrueType font files, bitmap font files, and National Language Support (.nls) files to the system. Adding a language group also adds registry values for Font Linking and installs scripting engines for Complex Script languages (Arabic, Hebrew, Indic, and Thai).