Basically like e-mail, if that helps.
You sign up on Protonmail, your buddy signs up on GMail. You can send mail to yourbuddy@gmail.com from youremail@protonmail.com. Proton Mail sees the address and sends the message over to GMail/Google. Despite there being 100s or 1000s of EMail services they all work together to form a singular service we call “email”.
That’s a lot of how it works basically. I’d add on community subscriptions to make it more complete. For example a user on piefed.social subscribes to !asklemmy@lemmy.ml. Once the first piefed.social user subscribes, lemmy.ml will begin sending piefed.social a message every time something happens on !asklemmy@lemmy.ml. So let’s say a lemmy.world user upvotes a comment in !asklemmy@lemmy.ml. lemmy.world sends that message to lemmy.ml, the host of the community. lemmy.ml then sends a message about the upvote to all servers with someone subscribed to the community, including piefed.social. In this way all servers show the same thing.
But yeah, the important part is that it works. How it works isn’t always something the end user needs to know.
























You absolutely do not need to come to the defense of the Nazis, especially clearly high ranking ones…