Main articles: Races in the Warcraft universe and Classes in World of Warcraft
Players create characters which serve as their avatars in the online world of Azeroth. When creating a character in World of Warcraft, the player can choose from ten different races and nine different character classes. The races are split into two diametrically opposed factions, the Alliance and the Horde.

The Alliance currently consists of Humans, Night Elves, Dwarves, Gnomes and Draenei (Draenei characters require The Burning Crusade expansion in order to be created.[16])
The Horde currently consists of Orcs, Tauren, Undead (specifically a faction that broke away from the Scourge called the Forsaken), Trolls and Blood Elves (Blood Elf characters require The Burning Crusade expansion in order to be created.)
In addition to the ten playable races there are many NPC races including (but not limited to) Goblins, Ogres, Murlocs, and Naga.

The nine available classes are Druid, Hunter, Mage, Paladin, Priest, Rogue, Shaman, Warlock, and Warrior. The Paladin class was previously only available to the Alliance, and the Shaman only available to the Horde. However with the release of Burning Crusade the Draenei (Alliance) are able to be Shamans and the Blood Elves (Horde) are able to be Paladins, thus removing the previous faction exclusivity. In the Wrath of the Lich King expansion, a tenth class known as the Death Knight will be added, which will also be the game’s first Hero class.[15] Classes are primarily limited by race: for example Night Elves can only be Druids, Hunters, Priests, Rogues or Warriors.