You have now complete the TeX mini course.

If you are interested in LaTeX The LaTeX Companion by Lyle Lamport is a great resource. By completing this course you should also be able to examine any of the macros built into LaTeX to better understand what they are and how they work.

If you want to find out more about the inner workings of TeX and its main companion for font creation you should check out The MetafontBook by Donald Knuth.