What three important traits? If you're talking of "inheritance, abstraction, and polymorphism" that you've mentioned, then I'd like to observe that inheritance

What three important traits? If you're talking of "inheritance, abstraction, and polymorphism" that you've mentioned, then I'd like to observe that inheritance is orthogonal to OOP, abstraction is essentially named definitions as a language feature (see Abelson, Sussman, Sussman, 1996, Chapter 1), and polymorphism, again, is found in many non-OOP languages, such as Haskell, for example.