Abilities in the game Final Fantasy Tactics Advance are in four categories: Action Abilities, Reaction Abilities, Support Abilities, and Combo Abilities. All three types of abilities are taught by equipment; Action Abilities are only learned from weapons, while weapons, hats, shields and armor are all capable of teaching a unit an R- or S- ability. While the equipment which provides the ability is equipped, a unit "masters" an ability by gaining enough Ability Points. If their equipment is changed before this occurs, their AP will remain where it was for that ability. Mastered abilities may be used at any time.