To manage Language groups and languages, go to the Language/Language Manager.
By default, you should have a language group named int with English language in it.
You can create a new language group or edit int language group.
Language group name will be in the URL and caption will be used by language selector page.
You can create a language group as a sub language group. To do that, you need to select the parent node in Belongs to section.
If you mark a language group as important, that language group will be shown as bold (Depends on theme).
Each language group can have none, one or more languages. Create a language group without language, if you want to have that as parent node of another language group.
Publishing
In publishing tab, if you set a date and time for Show From, It means the language group and all languages inside it, will be available from that date and time.
language groups and all sub nodes of that language group will be unavailable, before that date and time.