Remains internal state that depndes on the percpt history and thereby reflects at least some of the unobserved aspects of the current state. "What will happen if I do such-and-such" eg driver changing lanes needs to keep track of where cars are or were if it cant see anymore needs [[transition model]] and [[sensor model]] to work Together, the transition model and sensor model allow an agent to keep track of the state of the world—to the extent possible given the limitations of the agent’s sensors. ![[Screenshot 2023-03-10 at 6.33.21 pm.png]] seldom possible for the agent to determine the current state fo a partiallu oobservavle environment exacly. "what the world is like now" -> "best guess" ![[Screenshot 2023-03-10 at 6.33.32 pm.png]] --- #intro