The basic concept of OOPs are:

1. Inheritance- It is a mechanism in which a new class is obtained from an already existing class. As in Java, classes can inherit or procure the attributes and methods/processes of other classes. Thus a class that is procured from another class is known as a subclass, on the other hand, the class with the help of which a subclass is procured is known as a superclass.

2. Abstraction- This is among the significant concepts of the OOP (object-oriented programming) languages. The main goal of this is to manage complexity by suppressing irrelevant details from every user. Because of this, the user can implement more complicated logic on the head of the rendered abstraction without knowing or even considering all the unknown complexity.

3. Encapsulation- It can be employed to hide the data members along with member functions. This is to say that encapsulation implies that an internal representation of the object is usually hidden from a display outside of the definition of an object. Typically, particularly the object's personal methods can undeviatingly inspect or manage its fields.

BY Best Interview Question ON 19 Dec 2019