Does anyone know or can explain how the different Timelines work? How do they determine what ends up in them?

"Latest Activity," "Latest Posts," and "Latest Creation" all seem to have the same content in them. A mix of my own posts and those of people I'm friended to or following.

What determines what ends up in the "For You" feed? The "Discover" feed for me is blank. Is this something the server admin has to enable?

What determines what is in the "What's Hot" feed? I'm supposing this is not driven by an algorithm, but it also doesn't appear to be based on engagement (comments/shares/likes). Most of the posts didn't seem to have hashtags either, so it also doesn't appear to be based on a trending tag. And I checked and it's not the same as what appears in the "Global Community" feed, which appears to just be chronological.

I gather "What's Hot" is supposed to be like Mastodon's "Explore" feed? Which I seem to recall someone saying is based on "organic engagement" though I'm not sure anyone has said what the threshold is to get into that feed. I'm not following hardly anyone on Mastodon so I skip straight to "Explore" to find interesting people and stuff to read. If "What's Hot" here is similar great, but I'd like to know what criteria get a post into that feed?