They are pretty oblivious; There are 3 basic vocations, Knight, Archer and Mage. Knights are close combat fighters with high sustain, Archers are distance weapons users(bows, crossbows), with somewhere balanced survivability and Mages spellcasters, with high dps and burst magic damage, but they are the squishiest and highly dependent on mana class.
Also there will be promotion soon, where every vocation will be able to choice between two sub-vocations, f.e. Knight will have choice to become Crusader or Destroyed, crusaders are holy knights, with higher sustain, while destroyers are more as damage dealers.