Can you recommend a book for programming functionality for LaTeX?

Question

As a LaTeX newbie I want to start using it and extending it with my own stuff. I have some ideas for solutions for technical writing, which aren't solved until now. So I need a good book on LaTeX which looks at it from a programmers point of view. Like how does LaTeX actually work internally, how does all the stuff fit together, and where do I have to start touching code or adding code to get things working. Well you know what I mean right? :)

So is there any good book I should look at?

Answer 1

Internals: read Knuth's The TeX book. And then Knuth's TeX: The Program.

Latex's internals are not very exciting, but the code is free software: you can read it. But the key is understanding Tex.

Answer 2

I would recommend Guide to LaTeX by Kopka, Daly instead of the Knuth book because it is more up-to-date, and is very thorough for all features in LaTeX.

Of course, it is not for a complete beginner. Always start from the excellent (and free) guide, The Not So Short Introduction to LATEX2ε