This module exposes you to your first design pattern, the Singleton. The Singleton design pattern is used when there should only be one instance of a given class. It uses static, class methods and private
constructors to strictly control creation of new instances of the class.
In this module, you will learn:

1. The ten elements that distinguish a pattern
2. The intent of the Singleton pattern
3. When to use the Singleton pattern
4. The structure of the Singleton pattern
5. How the Singleton pattern is used in the real world

constructor: A pseudo-method that creates an object.