Object
- Encapsulates data and code
- Fields contain data
- Methods contain code for acting on the data
- Every object has its own copy of the data
- Same objects are typically grouped into a class
- Classes can also contain data and code shared among all objects
- Classes can be organised in an inheritance hierarchy
- Each derived class inherits the fields and methods of its base class
- Polymorphism allows objects of any derived class to be used as objects of the base class