Describe the State design pattern.

Describe the State design pattern.

The State design pattern is a behavioral design pattern that allows an object to alter its behavior when its internal state changes. It is used to model the behavior of an object based on its internal state, where the object's behavior is determined by a set of states and transitions between them. The pattern involves defining a separate class for each possible state and encapsulating the behavior associated with that state within the class. The object maintains a reference to the current state object and delegates the behavior to it. When the state changes, the object updates its reference to the new state object, effectively changing its behavior. This pattern promotes loose coupling between the object and its states, making it easier to add new states or modify existing ones without affecting the object's code.