AP
AP (Ability Points) are points that are used in the Kingdom Hearts series to equipped the game's characters with abilities. The overall AP can be increased by leveling up, using items such as AP Boost, or wearing equipment that will increase the overall AP. If the player does not have enough AP, they cannot equip certain skills until they have more AP or take off other abilities.
Kingdom Hearts
In this game, you can raise your AP through AP Ups
Kingdom Hearts: Chain of Memories
In Chain of Memories, AP is not used at all in Sora's gameplay, rather, it is replaced with what Sleights he can use, for both total Sleights and what he has equipped in his deck, and, in the case of Kingdom Hearts Re:Chain of Memories, what abilities he earns through the World Cards he ventures through (giving him abilities useable outside the battlefield). However, in Reverse/Rebirth, unrelated AP make an appearance as Attack Points in Riku's gameplay. The higher Riku's AP is, the stronger his attacks are.
Kingdom Hearts II
In this game the player can use AP Boosts on all characters including Sora, Donald, Goofy, and supporting characters. There are many AP Boosts in this game. AP Boosts can also be synthesized at Moogle shops.