Although classes are the centerpiece of object-oriented programming in Java, there are some other useful OOP features included in Java.
One of these features involves packages, which are used to organize classes into functionally-related groups. Interfaces are also an important part of Java's OOP support, and allow you to define the structure of classes.
This module discusses packages and interfaces, and also shows you how to control access to members of a class.

After completing the module, you will have the skills and knowledge necessary to:

1. Understand how packages are used to organize Java classes
2. Organize classes into packages
3. Control access to class members
4. Create interfaces that define the structure of classes