Oop

The ten main terms describing Object Oriented Programming:
1) Class -Defines the abstract characteristics of a thing (object), including the thing's characteristics (its attributes, fields or properties) and the thing's behaviors (the things it can do, or methods, operations or features).
2) Object -A pattern (exemplar) of a class. The class of Dog defines all possible dogs by listing the characteristics and behaviors they can have
3) Instance -One can have an instance of a class or a particular object. The instance is the actual object created at runtime.
4) Method -An object's abilities. In language, methods (sometimes referred to as "functions") are verbs. Lassie, being a Dog, has the ability to bark. So bark() is one of Lassie's methods.
5) Message passing -The process by which an object sends data to another object or asks the other object to invoke a method. Also known to some programming languages as interfacing. For example, the object called Breeder may tell the Lassie object to sit by passing a "sit" message
6) Inheritance -"Subclasses" are more specialized versions of a class, which inherit attributes and behaviors from their parent classes, and can introduce their own.For example, the class Dog might have sub-classes called Collie, Chihuahua, and GoldenRetriever.
7) Abstraction -Abstraction is simplifying complex reality by modelling classes appropriate to the problem, and working at the most appropriate level of inheritance for a given aspect of the problem.
8) Encapsulation -Encapsulation conceals the functional details of a class from objects that send messages to it.
9) Polymorphism -Polymorphism allows the programmer to treat derived class members just like their parent class' members.
10) Decoupling -Decoupling allows for the separation of object interactions from classes and inheritance into distinct layers of abstraction.
Above terms copied from wikipedia.org