Review

On-policy v.s. Off-policy

If the actor to train and the actor for interacting is the same, we call it on-policy. In other words, if the actor himself does training to gain experience, it is on policy; if the actor gains experience by watching other actors train, it is off-policy.

Difference between normal supervised learning

Reinforcement learning is unsupervised and it will solve the problem there is no standard answer(or humans also don't know the best way to solve).

The basic problems and parameters

All the purpose of the machine learning problem is to find a function, reinforcement learning is no exception.