What is the internal structure and operation of TeX/LaTeX?

Question

TeX

It is difficult to find something about the TeX device and related (detailed). I know about the use of METAFONT in it, etc., but I can’t imagine the process of creating a document.
Is there any literature devoted to the description of his work, the structure of the language, the stack of technologies?

Answer 1

Hmm ... to accuse someone but Donald Knuth of lack of detail ....
ISBN 5-900614-01-8 500+ pages
ISBN 5-8459-0382-3 560 pages with illustrations