A design pattern is a software solution that can be used over and over due to its ability to fix a common problem. There are a few different types of design patterns, such as creation, behavioral, and structural. Knowing and understanding a variety of design patterns can not only dramatically increase the speed at which you can code but also help in keeping your code readable for others who may have to jump into it.

This is a subject that is covered already by many books and is well outside the scope of this book. I bring it up because firstly we will be using one of the more popular design patterns: the Singleton, and secondly because I really wish someone had broached the design pattern subject a long time before they did.