A set of 3D polygons can be displayed on your screen using software and hardware that implements a "graphics pipeline". On many computer systems the graphics pipeline is implemented using the OpenGL library. Understanding how OpenGL works can help you identify which parts of the "rendering" process might be slow or which might be responsible for accidental misinformation, such as flickering polygons or a completely black screen.

The following snippet of OpenGL code is from a C program that calls the library to specify the color and location of a quadrilateral polygon.

The chart below depicts a graphics pipeline, the canonical description of which can be found in Computer Graphics: Principles and Practice by Foley, van Dam, Feiner, and Hughes. The following pages each explain a key element of the diagram.