This explains the fediverse with some examples of different instances
https://socialhub.activitypub.rocks/t/introduction-to-activitypub/508
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No, but some people are discussing about creating new logins, so I want to clarify. Thanks for the clarification.
I joined lemmy.world, because that’s the first one I came across. But now I can see the posts from many instances using voyager and Memmy. Now you can go and join any instance with interest you. That’s the beauty of it.