Chapter 4 begins the first of a two chapter series. We need to explore the syntax used to create classes and objects, and to manipulate such values once they have been created. But this is a large topic. We we break it into two smaller units. Chapter 4 discusses the static, compile time representation of object-oriented programs. chiefly this means the syntax used to create new classes. Chapter 5 discusses the dynamic, run-time behavior of programs. This includes message passing, and object initialization. Both of these topics are important, and both chapters should be understood before you begin further investigation of object-oriented programming.