What is object oriented programming

Object-oriented programming shifts the focus of attention to the objects, that is, to the aspects on which the problem is centered.
Central to C++ is object-oriented programming (OOP). As just explained, OOP was the impetus for the creation of C++.
Because of this, it is useful to understand OOP’s basic principles before you write even a simple C++ program.
An object representing an account in a program will have properties and capacities that are important for account management.
Object-oriented programming took the best ideas of structured programming and combined them with several new concepts. The result was a different and better way of organizing a program.
In the most general sense, a program can be organized in one of two ways: around its code (what is happening) or around its data (who is being affected).
Using only structured programming techniques, programs are typically organized around code. This approach can be thought of as “code acting on data.”
Object-oriented programs work the other way around. They are organized around data, with the key principle being “data controlling access to code.”
In an object-oriented language, you define the data and the routines that are permitted to act on that data. Thus, a data type defines precisely what sort of operations can be applied to that data.
To support the principles of object-oriented programming, all OOP languages, including C++, have three traits in common: Encapsulation, Polymorphism, and Inheritance.

Advantages of OOP

Object-oriented programming offers several major advantages to software development:

Reduced susceptibility to errors: an object controls access to its own data. More specifically, an object can reject erroneous access attempts.
Easy re-use: objects maintain themselves and can therefore be used as building blocks for other programs.
Low maintenance requirement: an object type can modify its own internal data representation without requiring changes to the application.

It gives stress on the data items rather than function.
It makes the complete program/problem simpler by dividing it into a number of objects.
The objects can be used as a bridge to have data flow from one function to another.
You can easily modify the data without any change in the function.