During character creation, you will choose a race and class, unless you decide to transfer a character over from Dragon Age: Origins. Not only do race and class give different bonuses to different stats, but they may affect how certain characters in the game interact with you. Here are brief descriptions of the three races and classes.
Races
Human: The most numerous, yet the most divided of all the races. Only four times have they ever united under a single cause, the last being centuries ago. Religion and the Chantry play a large part in human society. It distinguishes them culturally from elves and dwarves more than anything else. Humans can be warriors, rogues, or mages.
Elf: Once enslaved by humans, most elves have all but lost their culture, scrounging an impoverished living in the slums of human cities. Only the nomadic Dalish tribes still cling to their traditions, living by the bow and the rule of their old gods as they roam the ancient forests, welcome nowhere else. Elves can be warriors, rogues, or mages.
Dwarf: Rigidly bound by caste and tradition, the dwarves have been waging a losing war for generations, trying to protect the last stronghold of their once-vast underground empire from the darkspawn. Dwarves are very tough and have a high resistance to all forms of magic, thus preventing them from becoming mages. As such, dwarves can only be warriors or rogues.
Classes
Warrior: Warriors are powerful fighters, focusing on melee and ranged weapons to deal with their foes. They can withstand and deliver a great deal of punishment, and have a strong understanding of tactics and strategy.
Mage: As dangerous as it is potent, magic is a curse for those lacking the will to wield it. Malevolent spirits that wish to enter the world of the living are drawn to mages like beacons, putting the mage and everyone nearby in constant danger. Because of this, mages lead lives of isolation, locked away from the world they threaten.
Rogue: Rogues are skilled adven turers who come from all walks of life. All rogues possess some skill in picking locks and spotting traps, making them valuable assets to any party. Tactically, they are not ideal front-line fighters, but if rogues can circle around behind their target, they can backstab to devastating effect.