On top having the ability to choose from being a Hunter, Warlock, or Titan, Bungie announced that you can also select your race. The three races talked about were Humans, Awoken, and Exo.
From what it sounds like you will get to mix and match these races with your guardian class. This means you could have a Human Warlock or even an Awoken Titan.
Described as being relatable, tough, and uncomplicated.
Ex. Military, Sports Stars, Action Heroes
Described as being exotic, beautiful, and mysterious.
Ex. Elves, Vampires, Ghosts, and Angels
Described as being sinister, powerful, and tireless.
Ex. Undead, Master Chief, and the terminator