I'm so confused, I don't even know where to ask this stuff. Here are my questions, hopefully it helps others in the future:

1. I see a bunch of different "Lemmy's" here. What are these called? "Flavors" of lemmy? Lemmy "websites"? Lemmy "instances"?

note: I'll call their collective entirety as "Lemmies", for the remainder of the post

2. If I created an account here on lemmy.ml, (obamacares), does that account also exist on other "Lemmies"?

3. Do posts and comments on this Lemmy also exist on other Lemmies?

4. If one happens to be banned from a specific Lemmy instance: does one also get banned from other Lemmies?

5. In case the answers to the past 3 questions was "No": then what is the relationship between the different "Lemmies"?

6. How are those Lemmy websites stored and served? Is it just a machine the person who created the website maintains — or is there more to it? (some kind of decentralized collaborative server pool, or some blockchain stuff, idk)

7. How much "privacy" can I expect inside these Lemmies? For instance, if I talk to some user through dm's, can anyone else see our messages?

8. If I delete a post or comment: is it gone for good — or will it linger for the eternity in some internet server somewhere?

I probably have more questions, but I forgot now.