Hi Cron
If you don't understand Windows permissions, it might help of you explain why you're trying to learn. Is it for education or do you have a problem to solve?
It's a big subject and if you're not a geek, it can appear intimidating. Starting from one of the above may help folks to guide you. In general, you only need to futz around with permissions if you are fixing a problem or hacking something.
What's you need?
Cheers