Classes fall under two familiar main categories: fighters and spellcasters, then branch out into basic and final classes, as illustrated in the "tree" diagram in the gallery below. Players can choose the path of Warrior, Rogue, Mage, or Healer, specializing further into eight "final classes" as well, as they advance through the game.
Once players reach level 20, they will be able to choose their "path in life", deciding on a specialty. There are relevant NPCs for each path in the main city for you to talk with once you've chosen. The class system, while not unfamiliar, is interesting and should serve to help players become familiar with their chosen class over time.
Take a look at the gallery including the class tree, and be sure to check out the Tales of Fantasy site for more information.