Fediverse

Hello all!

Came to Lemmy from Reddit as I wanted to be a part of helping the fediverse & Lemmy grow. As someone mentioned on here "be the change you want to see". So here I am! However I'd like to fully understand the fediverse so I can explain it to others and help them join.

I understand the concept of the fediverse but what I'm struggling with is the instance part. I know an instance is a spun up server, and I'm assuming it's a copy of the lemmy source code, for example, which means it is its own contained version of Lemmy. This instance sets it's rules, creates its own sub communities etc. You join the instance that relates to you the most.

But does that mean you can only post in that instance? I know you can follow users etc from another instance, but you can't post in their instance without migrating your account there? Is this the same for mastadon, where you can read / follow users, but cannot post?

The example im thinking of is say there is a sub community on your instance for gardening, but you find out another instance has a bigger, more involved sub community for gardening. You want to participate there, that would mean you need to join that instance to do so? Would that mean multiple accounts for multiple instances?

If there is a handy FAQ, or a video, that helps explain this that would be great!

Really excited to be a part of this and looking forward to understanding it better.