Abstraction has allowed us to define a common set of functionality that is to be shared among all the classes that derive from the abstract classes. The difference between inheriting from the abstract class and a normal class is that with an abstract class, you have to implement all the methods defined in that abstract class.
This makes the class easy to version and change. If you need to add new functionality, you can do so by adding that functionality to the abstract class without breaking any of the existing code. Visual Studio will require that all inherited classes implement the new method defined in the abstract class.
You can, therefore, be assured that the change applied will be implemented in all your classes that ...
