10.2. Objectives of This Chapter

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By the end of this chapter, you should

1. Understand how we can use polymorphism to allow objects of different classes to be treated interchangeably by the user of these classes,

2. Understand how to create a polymorphic object that allows polymorphism to be used safely in application programs without exposing the class user to the hazards of pointers, and

3. Understand how to use reference counting to allow one data item to be safely shared among several users.