Combat in MMOs differs from game to game. Some games use a traditional system of combat where the player has an abundance of spells and abilities lined up in several hotbars like in World of Warcraft. With cooldowns and global cooldown, players are limited to certain abilities depending on when they last used it. For the interim, the player must let the character auto attack. On the other hand, some games use active combat with positional attacks and active blocking mixed with spells and abilities like in Age of Conan.