The three fundamental features of an object oriented programming language are written above.
1. Inheritance:It is the mechanism when a class acquires the properties of some other class.The class which acquires the properties is called the child class and the class from which properties are inherited is called the base class.
2. Data encapsulation is clubbing different types of data in one place.That what class does .It can contain different data types in one place and those variables can be public ,private or protected.
3.Polymorphism it the property when an entity is processed in more than one form.Either be it run time or compile time polymorphism .