There are four distinctive languages in the world of Atharon: Senex, Basic, Dracon and Rhis
Senex is the very first language that came into existence, the ancient language of the Sentinels. It's a complex and extremely difficult language to master, embedded into the essence of any and all sentient beings of the world. Therefore, if an individual can speak Senex, he should be able to commune with any sentient creature. Although the language is long forgotten and considered by many to be obsolete, it is still treated as living tongue within a single country: The Atharon Empire.
Basic is the common language and the one all humans understand and speak different dialects off. It is by far the easiest language to master and it's officially considered the main language of the entire world, with some minor exceptions.
Dracon is the native language of the continent of Draconia and it's somewhat similar to Basic, hence why many tend to debate which of these two languages was the foundation for the other.
Rhean is the native language of the people of Rhea. Since it was conceived and evolved without any outside influence, the Rhean language stands out as the only unique language in the world. It is the only official language on Rhea and it isn't used anywhere else in the world.