@dcabungcal and @r0cknroll, Abstraction is not a part of OOP, where did you get that? Maybe you mean about Abstract classes? Or Data abstraction?
I know some websites explaining about Abstraction as part of OOP or even books out there, but this has been corrected by Microsoft on their product line C#, where it clearly explains the beauty of Abstraction in relation to interfaces but not inside OOP, other than that we have Procedural Programming, Generic Programming. Well, I guess this depends upon the person and his ways of getting things to learn quickly.
Please take note that C language or C++ is not the same, even C with classes and C++ (OOP) is totally different, its structure and the way it’s been implemented is totally different, I guess you have to figure this out…