@b0rk
Saved. In case I ever get lost inside a git repository and need a map to find my way home.

Seriously - if I ever find that I need a tool that doesn't exist and need to write it myself.

There are two kinds of objects I didn't see mentioned - merges and packed objects. I'm guessing that merges look just like commits, and pack objects are "binary" but I have not looked.

Also, diffs aren't explained, but I believe they don't actually exist, though then I don't understand how the packed history is often smaller than the checked out head.