(Inheritance, Overloading and Overriding are used to achieve
Polymorphism in java).
Polymorphism manifests itself in Java in the form of multiple methods
having the same name.
In some cases, multiple methods have the same name, but different
formal argument lists (overloaded methods).
In other cases, multiple methods have the same name, same return type,
and same formal argument list (overridden methods).
