Learn Web Development with Python

Polymorphism – a brief overview

The word polymorphism comes from the Greek polys (many, much) and morphē (form, shape), and its meaning is the provision of a single interface for entities of different types.

In our car example, we call engine.start(), regardless of what kind of engine it is. As long as it exposes the start method, we can call it. That's polymorphism in action.

In other languages, such as Java, in order to give a function the ability to accept different types and call a method on them, those types need to be coded in such a way that they share an interface. In this way, the compiler knows that the method will be available regardless of the type of the object the function is fed (as long as it extends the proper interface, ...