What is object-oriented programming

Object-oriented programming (OOP) is a programming methodology based on representing a program as a collection of objects, each of which is an instance of a certain class, and the classes form a hierarchy of inheritance.

  • Object Oriented Programming uses objects rather than algorithms as the main logical building blocks;
  • every object is an instance of a certain class
  • classes form hierarchies.

A program is considered object-oriented only if all three of these requirements are met. In particular, programming that does not use inheritance is called programming using abstract data types, rather than object-oriented.

According to the OOP paradigm, a program consists of objects that exchange messages. Objects can have state, the only way to change the state of an object is to send it a message, in response to which the object can change its own state.


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