Linus Torvalds, creator of git:
You can actually see how it all took shape in the git source code repository, except for the very first day or so. It took about a day to get to be “self-hosting“ so that I could start committing things into git using git itself, so the first day or so is hidden, but everything else is there.
You can see all of the commits on GitHub. Here is the first page (as of today) and the first commit.