What do I need to read to understand how git works?

Question

I would like to understand the way git works from a architects point of view. How are files stored, how are versions kept and how do changes happen (branches, merges, etc.)?

I am not searching for information how to use it. (I already found a lot of pages with tutorials.) But I did not find any "behind the scenes" details, that would make me understand.

Answer 1

The git source code. :-)

Answer 2

http://git.or.cz/

Answer 3

I found this site when I googled "git architecture": http://speirs.org/2007/07/19/a-subversion-user-looks-at-git

Git has a mailing list: "[email protected]&body=subscribe%20git" (http://git.or.cz/#community)

And this wikipedia article may be helpful: http://en.wikipedia.org/wiki/Git_(software)

Answer 4

Wikipedia might get you started.

I do remember encountering some documents describing some of the internal architecture, so I know that they are out there. I just can't remember where they were...

Answer 5

I've found the Git User Manual to be very enlightening.

Answer 6

There's a good Google tech talk: Linus Torvalds on git

OK, it's not something to read but it does cover some of the Git internals and design philosophy.

Answer 7

http://eagain.net/articles/git-for-computer-scientists/

http://www.loria.fr/~molli/pmwiki/uploads/Main/gitmanual.pdf Chap 7

http://www.newartisans.com/blog_files/git.from.bottom.up.php

Answer 8

This talk by Randal Schwartz gave me a pretty good overview.

Answer 9

I found these pages useful :

• gitcore-tutorial
• git concepts from the user manual
• git repository layout

Answer 10

Check out Git from the Bottom Up

Answer 11

One day I actually sat down and read the entire Git User's Manual. Turned out to be a good idea -- the manual is very helpful, explains a lot, and is quite clear and provides useful examples.

Answer 12

The US$9 100+ page PDF book from PeepCode called Git Internals is fantastic. It's well written, uses great, clear visuals and is also a quick read. I absorbed as much free online material as I could but this book put me over the top.

Answer 13

There are some interesting documents on the Documentation/technical directory of the git source code.

Answer 14

For me, the following three resources were very, very helpful, in this order:

1. The Thing About Git explained why I should even care

2. Git Magic explained how to get started

3. Git The Basics [pdf] explained - graphically, and in detail - what happens when I add, remove, merge, etc.

Answer 15

The Git Internals ebook has already been mentioned. I will point out that its author, Scott Chacon, gave a fantastic presentation about git at RailsConf 2008 that covers much the same ground as the book.

Said Scott now maintains http://git-scm.com/, which includes the Git community book, which is more of a usage tutorial than a technical description, but does include both a nice conceptual overview of the git data model in the introductory chapter and a detailed one in its closing chapter.

Answer 16

To understand how git works you need to read Pro Git book, fully available online for free.

Written by Scott Chacon, one of the guys behind GitHub.

I wrote my opinion about the book in a review at Amazon.