A CMS instance is set up with a default language. There can only be a single default language at any one time. To set a language as the new default language, simply click the star icon next to any enabled language.
When a language is enabled, it becomes part of the value management process as described here. To enable a new language, browse the list of languages in the Disabled Language section and simply click the language name.
Once a language is enabled, it must be activated by clicking the run icon. Similarly, a language can be temporarily deactivated by clicking the pause icon.
When it is decided that a language is no longer used, it can be disabled entirely by clicking the “x” icon.