In object-oriented programming (OOP), an interface is a contract or a set of methods that a class must implement. It defines a common set of methods that a class must provide, but it does not provide any implementation details. An interface can include both method signatures and constants.
Interfaces are used to define a common behavior for a group of related classes, and to provide a way for objects of different classes to be treated polymorphically. A class that implements an interface must provide an implementation for all of the methods declared in the interface. A class can implement multiple interfaces, but can only inherit from one base class.
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