HELLO NEW USERS!
Mastodon is server software. Anyone with a web server can set up a Mastodon instance.
Here's a guide to Mastodon, with many frequently-asked questions: https://github.com/joyeusenoelle/GuideToMastodon/
If you're on the mastodon.social instance, here are our rules: https://mastodon.social/about/more
If you're on another Mastodon instance, you can usually find their rules at <instance URL>/about/more, just like mastodon.social's.
Server run by the main developers of the project It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!