Ttrpg.network, which you joined, is one of many websites that can all communicate together with a common web protocol. This process is called federation and all of those sites together are called the fediverse. So for example, I’m logged into slrpnk.net right now but because both of our sites (called instances) are federated, I can view and comment here, and you’d be able to do the same on any communities hosted on slrpnk.net. You may have heard of mastodon which is more of a twitter alternative but it’s also part of the fediverse, so you should be able to use your account here to view and interact with mastodon content as well if you wish.

It’s a pretty clever system and while there are hiccups here and there, for me it has been a good replacement for Reddit. We just need more users and content to really get things going.

One explanation that really helped my grasp this I saw a while back was that this is very similar to how email works: Lots of different domains/providers/websites, but ultimately they are all connected and interact with each other.