Summary
As I previously mentioned, there are entire books written on design patterns, and so I have no expectations that you have managed to learn everything you need to know by reading this chapter only. What I do hope, though, is that you now have an understanding of what design patterns are, you have a good idea about the broad categories of design patterns, and I'd like to think that you might have got your head around a few of them. I suspect you recognize some of them from code that you are already used to working with. The best thing to do now is to continue writing code, but as you are architecting things, just take a moment to wonder whether it would be a good idea to use one of these established patterns, and then give it a go.
In the next chapter, we're going to do a deep dive into a design pattern I am almost certain you have already come across: MVC.