That really helps, thanks :) There are still some things I would like to better understand though. If I'm in a house, it's easy to see which windows are open and it's obvious when I'm looking through a window at a different house. How does that work in reality?
For example, here we are on kbin.social looking at this post on ELI5. If my friend is on Lemmy.world will they see this post in their ELI5 or do they have to know to visit kbin.social to see it? If they are looking for good explanations of how the fediverse works, how would they come across this post? Do they have to look on every instance until they happen to find it here?