What is OO programming?

Object-oriented programming (OOP) is a programming paradigm based on the concept of "objects", which can contain data, in the form of fields (often known as attributes or properties), and code, in the form of procedures (often known as methods). A common programming technique involves creating reusable "objects", instances of which can be easily employed in other programs or instances. Key concepts of OOP include encapsulation, inheritance, and polymorphism.