What is polymorphism, what is it for, and how is it used?

Question

What is polymorphism, what is it for, and how is it used?

Answer 1

Polymorphism in coding terms is when your object can exist as multiple types through inheritance etc. If you create a class named "Shape" which defines the number of sides your object has then you can then create a new class which inherits it such as "Square". When you subsequently make an instance of "Square" you can then cast it back and forward from "Shape" to "Square" as required.