The basic human tongue that developed in Reman before Humanity ever gained the technology to sail the wide expansive seas. It has changed an evolved over time, but all human civilizations speak some derivative of this language.
The main dialect sounds like modern English with a Spanish accent. Other dialects tend to sound like other Latin-based modern languages.
All of the various dialects that derived from Reman share a written script, though pronunciation can vary wildly between cultures.