Unity UI Where is the comprehensive documentation on Layout Groups and related components?

Hello!

Whenever I use a content group, I always check and uncheck boxes until things almost look the way that I want, but I never understand what I'm doing. I really want to understand how the layout groups work. Where is the thorough documentation? It doesn't have to be official, I just want to learn what every checkbox and setting here does:



I also want to learn what every checkbox and setting here does:



And I also want to learn what every checkbox and setting here does:



These components interact with each other, so in my opinion, you can't really understand one unless you understand them all. I want to learn these so thoroughly that when I finally get something looking the way I want, I can say, "That makes sense."

Where can I find thorough documentation on Layout Groups, Layout Elements, and Content Size Fitters?