Benefits of OOPs

Reusability: In OOP’s programs functions and modules that are written by a user can be reused by other users without any modification.
Inheritance: Through this we can eliminate redundant code and extend the use of existing classes.
Data Hiding: The programmer can hide the data and functions in a class from other classes. It helps the programmer to build the secure programs.
Reduced complexity of a problem: The given problem can be viewed as a collection of different objects. Each object is responsible for a specific task. The problem is solved by interfacing the objects. This technique reduces the complexity of the program design.
Easy to Maintain and Upgrade: OOP makes it easy to maintain and modify existing code as new objects can be created with small differences to existing ones.
Message Passing: The technique of message communication between objects makes the interface with external systems easier.
Modifiability: it is easy to make minor changes in the data representation or the procedures in an OO program. Changes inside a class do not affect any other part of a program, since the only public interface that the external world has to a class is through the use of methods;

The typical programmer’s advantages are:

Multiple-inheritance, where classes can inherit from multiple super classes.
Multi-method dispatch, where operations can be specialized not just on a single object, but on any of the arguments for the operation, or any combination of those arguments.
Method combination, in which the means by which several applicable operations to a particular set of arguments can be combined, is itself an object-oriented specification, definable by the programmer.
Operations that can specialize on particular instances of classes, rather than on just the broad class of the arguments.
Shared class variables (slots, attributes) that are shared by all instances of a class, in addition to instance variables which are unique to each instance.
Specification of the creation operation for instances of a class as an object-oriented program, definable by the programmer.
The behaviour of operations on objects (methods) are themselves defined as first-class objects, which can be specialized by the programmer.
Access to classes themselves as first-class objects. The objects which define the behaviour of classes are themselves classes, usable directly by the programmer.