State is the information a system, program, model, or environment retains at a given point in time. In reinforcement learning, state often refers to the representation of the environment used by an agent to choose actions.
In information technology and computer science, a program is described as stateful if it is designed to remember preceding events or user interactions; the remembered information is called the state of the system.
In reinforcement learning, the parameter values that describe the current configuration of the environment, which the agent uses to choose an action.