We have used only some basic functions of the pygame.display and pygame.event modules. Pygame provides much more functionality, including:
Drawing 2D geometry
Drawing text
Managing groups of drawable AI entities (sprites)
Capturing various input events relating to the window, keyboard, mouse, and joysticks/gamepads
Creating custom events
Playback and synthesis of sounds and music
For example, Pygame might be a suitable backend for a game that uses computer vision, whereas HighGUI would not be.