Over the course of this chapter, we will be expanding on our twin-stick shooter by adding additional UI elements that will include a main menu, a pause menu, and an options menu and will give us the ability to restart our project. This chapter uses the UnityGUI system that existed before Unity 4.6. Even though the new system does have its advantages, the old system is still quite useful to learn. It's still the only way to create UI elements for the Unity Editor (which you can use to create plugins that you can sell on the Asset Store), and it has a much larger amount of documentation out there to help new users.