Action Points (or AP) is a game mechanic governing the number of things a character can do during one combat turn in Fallout and Fallout 2. In Fallout 3 and Fallout: New Vegas, Action Points are used to attack in V.A.T.S.. In Fallout 4, Action Points are used to attack in V.A.T.S, hold your breath while using scopes, sprint, and operate the jetpack.