1)In object-oriented programming, polymorphism (from the Greek meaning "having multiple forms") is the characteristic of being able to assign a different meaning or usage to something in different contexts - specifically, to allow an entity such as a variable, a function, or an object to have more than one form. Polymorphism is a feature of object-oriented programming languages that allows a specific routine to use variables of different types at different times
Polymorphism is the ability of a programming language to present the same interface for several different underlying data types
Polymorphism is the ability of different objects to respond in a unique way to the same message
2)Suppose if you are in class room that time you behave like a student, when you are in market at that time you behave like a customer, when you at your home at that time you behave like a son or daughter, Here one person present in different-different behaviors.