There are 5 main languages on the Disc: Agatean, Djelian, Ephebian, Morporkian, Uberwaldean.
Each of these is split into Spoken and Written.
All characters begin with 100|100 in the language of the nationality they have chosen to start with. To gain any skill in another language a player must go to one of the many language schools and enroll in lessons. These will only give a basic understanding of a language and to develop their skills further a player must listen to and read a language.