Found a good image explanation of this whole thing.
Edit: update image to use light theme.
Credit goes to @ulu_mulu@lemmy.world
This is really great! I've also been quite lost but am enjoying the learning process!
One thing I've just learned is that all the different instances don't neccessarily 'federate' with each other in real time (there can be some lag in content showing up in your instance) or at all. Only instances your instance federates with sync up? I think? :-) I see beehaw.org have had to cut ties to a couple of instances to help with the flood of new users and content happening right now. It seems while you can still view their content from your instance you can't comment or post to it? I think? :-)