Jakub Narebski [off-list ref] writes:
If you didn't find sufficient description of underlying concepts behind
git in "Git User's Manual" (distributed with Git), "Git Community Book"
or "Pro Git", take a look at the following documents:
* "Git for Computer Scientists"
* "Git From Bottom's Up"
* "The Git Parable"
...
It is documented, see referenced mentioned above.
I actually would want ourselves step back a bit and make sure that anybody
who is completely new to git won't get confused with the concepts after
s/he reads our "Git User's Manual" and nothing else. Listing five or six
documents and "you'll find information somewhere among these" *might* be
the best thing we could do at this very second, but we should strive to do
better than that.