What is oUF
 

Forgive me if this has already been asked, but what is oUF and what does it stand for? Where can I find more information on it? I'd like to know what the different variables mean so when I go poking around in the code I know what I'm doing. I've been using a version of it in a Diablo themed add on for years now and have been wondering. My only coding experience is html and css so forgive me if these seem like stupid questions

If you go to the main section for addon sections and scroll down to featured addons you will see it there (here).

It stands for otravi unit frames.
It's a framework for building unit frames as well as nameplates.
There's plenty of documentation in the oUF section, GitHub and not to mention there's tons of layouts to look over and see what people are doing.