Class modules in Visual Basic 4 gave you the ability to create and use objects for the first time. Visual Basic 5 enhanced the features of class modules and added many new object-oriented programming (OOP) capabilities to the language. Surprisingly, Visual Basic 6 does not add a lot of new object-oriented features to the language. However, it's clear that the solid object-oriented foundation laid in previous versions of Visual Basic will play an increasing role in the use of Visual Basic 6 to create today's, and tomorrow's, advanced applications.
If you aren't yet familiar with these object-oriented programming features, now is a great time to jump on the bandwagon! Throughout this book I've attempted to provide working examples of object-oriented code and modules, in such a way that you aren't overwhelmed by this new way of organizing and structuring your applications. A whole new set of terminology comes with object-oriented programming. If the terms polymorphism, friend functions, encapsulation, interfaces, collections, and so on, are not all that clear to you, don't panic! I explain these concepts in more detail later and provide working examples to help you get a firm grasp on this important new part of the language.