@BeardedPip It's what links with Mastodon. If you go to a community's Microblog page, you'll see a bunch of posts that you can trace back to Mastodon. How it shows up in that community is because the community looks for certain #tags. If a Mastodon post has that #tag and the community is accepting it, then that post will show up in the Microblog for that community.
NotTheOnlyGamer