The giant font doesn't make it any easier to understand. Stuff like 'your local repository consists of three "trees" maintained by git' only makes sense to people who already know how git works.
A repository for what? Is this a folder on my computer somewhere? Should I be moving code into this folder? No idea.
In order to make this tutorial helpful, why not take a simple project and get it working under Git?
For example, let's say right now I have a folder that consists of a single source code file like testapp.php, a README.txt, and then a content folder with some images in it. How can I take this mini project and start using Git to manage my code?
I'm seriously that "beginner" when it comes to Git. I do not understand it at all. Maybe I'm not your audience. This tutorial was FAR from simple IMO.
Honestly, I'm not even sure you need to talk about "trees". The first chapter of Pro Git doesn't mention them at all, and this section describes the working dir, the index and HEAD without using the word: http://progit.org/book/ch1-3.html Instead he talks about "snapshots" and "stages".