Getting Started on Lemmy

https://startrek.website/post/55

Getting Started on Lemmy - Star Trek: Website

Okay. I've learned a little bit, enough to ask questions. Where should I go to post my questions/thread about waves hand all this? At this point, my questions are very ELI5, with answers (hopefully) in the form of tiny, manageable bites, not walls of text. So far, I know I signed up for and can post on a Community, Star Trek specifically, LLAP. And, that the Fediverse is not a new name for the United Federation of Planets. And ... yeah, that's about it.
This is as good a place as any. We're all learning as we go.

Thanks. I just hit the wrong button and lost my reply to you. Shaka, when the walls fell. Giving it another go.

I'm deciphering an image whose original post I've lost in a sea of Lemmy links I've been reading and bookmarking. Image link is below. So, Lemmy is an umbrella for instances (servers), which in turn can host (I'm not sure if host is the right term) other instances? Is Star Trek an instance like a mini-reddit, or an, I don't know what to call them, an instance like a subreddit within the mini-reddit?

The image I mentioned:

https://lemmy.world/pictrs/image/0006c2db-13c6-406e-97e7-6e274fddf355.png

If you've been on the Internet a long time, good analogies seem to be like email servers or (back in the day) Usenet servers. There can be lots of servers, and you get an account on one, but then you can post and read between all the servers. Like being on gmail but emailing people and reading emails from them at other places. Or back in the day, like being on your ISP or university's Usenet server, but reading posts from other servers and posting things people on other servers can read.