Abstraction is the process by which data and programs are defined with a representation similar to its meaning (semantics), while hiding away the implementation details. Abstraction tries to reduce and factor out details so that the programmer can focus on a few concepts at a time.

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Abstraction means datahideing.That means we use the object wethout knowing the source code of the class.

Encapsulation is the hiding of information in order to ensure that data structures and operators are used as intended and to make the usage model more obvious to the developer.

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Encapsulation is a mechanism by which we desigm our class such a way that if  we change our class in fuature, we dont need to change the classes which are depending on our classes.

Inheritance is a way to compartmentalize and reuse code by creating collections of attributes and behaviors called objects which can be based on previously created objects. In classical inheritance where objects are defined by classes, classes can inherit other classes. The new classes, known as subclasses (or derived classes), inherit attributes and behavior (i.e. previously coded algorithms) of the pre-existing classes, which are referred to as superclasses.

Overloading is the concept of having functions of same name, but different signature in same class. They are differentiated by the compiler by their signatures.

Polymorphism is a programming language feature that allows values of different data types to be handled using a uniform interface. The concept of parametric polymorphism applies to both data types and functions.