Object Oriented

To be considered a true object oriented programming language the language must support the following:

Encapsulation - Being able to hide parts of the implentation from being seen from the outside. You can use the "private" keyword to prevent variables from being seen from outside the class. The separation between interface and implementation. You can encapsulate the object and it is only made available to the outside through a well defined interface.

Abstraction - This focuses on the interface and gives you the ability to create an abstract representation of an object or concept and therefore being able to hide the complexity and logic. You can use the "private" keyword to prevent methods from being seen from outside the class.

Inheritance - Extends the functionality but can't remove it. The ability to derive new classes from existing classes. Allows you to treat objects of a derived type as objects of its base type. This can be used to create specialization.

Polymorphism - Creating routines that can operate an objects of different types that is handled with late binding and multiple interfaces. Allows you to manipulate objects of related types as though they were of a common type.

Association
Relationshipd between independent or loosely coupled objects.

Aggregation
One object is made up of other objects (a parent-child relationship)

Composition