Introduction

In this lesson you’ll dive deeper into Object-Oriented Programming by learning about base classes and how they can ensure consistency and abstraction from the rest of the system. You’ll also learn about static members and static methods; what their power is and their limitations. Finally, you’ll learn about method overloading and method overriding and how they can solve what would appear to be a complex challenge, in almost no effort.

You’ll continue working on the same ContactCard app you started on in the last lesson. I recommend that you use the starter playground with this lesson and not continue from the code of the last lesson. The Playground file is a little bit more organized and is using a separate Swift file to define ContactCard and the type is now a class type not a structure. Structs can’t be used with inheritance which you’ll be doing in this lesson.