Learn the four types of polymorphism in Java, then start using subtype polymorphism to execute different forms of the same Java method.

Compare inheritance and composition, the two fundamental ways to relate Java classes, then practice debugging ClassCastExceptions in Java inheritance.

We also learned how to use inheritance and polymorphism to speed up our code implementation time and to isolate bugs, which makes our code maintenance tasks much easier.

Today, C++, C#, Java, Visual Basic.NET and Python are popular object-oriented languages. The following compares basic OOP terms with traditional programming. See object-oriented DBMS.