‘Information’ looks at the role information plays in games. When players hold imperfect information game theorists need to keep track of what is known, and when. Playing a game like poker with a minimax strategy is neither profitable nor fun. Success depends on changing what your opponent thinks they know about your hand through bluffing. Hobbes outlined four properties: body, passion, experience, and reason — which give rise to a player's ‘type’. Rational Analysis assumes that player types are common knowledge, but this is not always so in the real world. A player can signal their type to other players. This generally involves a costly action as a show of strength.