In this chapter we’ll create a basic graphical user interface (GUI) system for CMOD. This includes a main menu and a HUD (head-up display). The main menu will appear when the user presses the Escape key on the keyboard, allowing him to restart, load, save, and exit the game. And the head-up display will continually show Player health, as well as the ammo status for the active weapon. In creating the GUI, we’ll explore a range of subjects, including screen dimensions, the aspect ratio, widgets, anchoring, GUI scaling, and resolution independence. As always, these subjects apply practically, not just for CMOD or Unity specifically, but for game engines and games, as well as software and web sites in general. So, let’s get started with creating GUIs.