PHP start OOP in PHP 4 and a stable model of Object Oriented Programming (OOP) introduced in PHP 5 in 2004. We all making applications in procedural programming and want to move to OOP way, Object Oriented is an style of coding that allows programmers to group similar tasks into classes, using Object Oriented Programming you can easily maintain your code. Before going to explain OOP let me give you some real example like universe made of different objects like sun, mars, moon etc, a car made of different objects like steering, engine, break etc.