Functional PostScript Tutorial
What I have presented so far should keep you amused for a while. But once you have worked through all the examples, you may want to look up the following topics in the reference manual:
FPS Tutorial Content: Intro and The Idea | Getting Started | Paths and Pictures | Show and Channels | Transformation | Composition | Glyphpaths | Style | Color | Colormap | Clipping | Glyphnames | Other Topics