Manual:$wgLang

Details
The user language object is the language object selected in user preferences.

It is one of two global language objects, the other being  .

See the page  for more information.

is initialized towards the end of setup; some hooks are called earlier than that and should avoid using it. When in doubt use  to check.

Often used Methods
This is not an exhaustive list, view class above to see a complete listing.

delimit a list of strings according to the conventions of the user's language

return the user's language code, for example "en"