The OpenGL window is (-1.0, -1.0) in the bottom left to (1.0, 1.0) in the top right.
A color with 32-bit float parts from
An image that can be drawn using the
An OpenGL window for displaying graphics. Also the object through which you'll receive input events (mouse, keyboard, etc.)
Whether a button was pressed or released
Abstracted button values you may receive (arrow keys and WASD keys combined into directions, for example)