Mastodon for Metalheads (opens in new tab)

Not intentionally. Mastodon is also a name of a Twitter-like social network. So the title here makes perfect sense for people like myself who hadn't heard of the band with the same name.

This is just one of those occasions where name collisions happen through nobodies fault.

Mastodon is a decentralized, free software alternative to Twitter. Also see: https://joinmastodon.org

I knew that, I run one. (Please don't join it.)

But I don't randomly post it to HN, and it looks like the author of this post is the admin too.

> If all are connected, why care for which server I connect to?

Mastodon is like E-Mail: You chose who hosts your profile. YOu can send messages to people on other servers, but still the server which hosts your account, is your "home server": If it goes down, your account/profile is lost.

Also choosing your Mastodon server is about your personal interests: Mastodon servers have local timelines, which only show posts by users on the same server. These timelines often are topic related. E.g. on metalhead.club you will find more metal music content compared to e.g. mastodon.social.

Mastodon servers / instances group users by interest and still let all Mastodon users communicate with each other.

Btw: I don't consider the terms of use "leftist". They are quite neutral and generally "human friendly". Metalhead.club is not political, but the Terms of use try to prevent hate speech.

Each server can have its own rules and can choose to block whichever other servers it wants. But besides that, they're pretty similar. The big draw of Mastodon is that it doesn't really matter that much which server you use. If the admin of your server starts doing stuff you don't like, you can move to another server and direct your followers there. (Compare this to centralized social networks like Twitter and Facebook. If you don't like what their owners do, your only option is to leave and lose access to the network entirely.)

In addition to the other replies: one big draw of specific servers/instances is the local timeline, a feed of every post on a server. While you can connect to anyone, discovering new people is much easier on the same instance. For this reason people prefer small, specific instances.

The Mastodon culture is also fairly opposed to large instances. Mastodon.social (the "flagship") is widely criticised for allowing itself to grow much larger than other instances. The community prefers small, homely intantances, median size is probably about 500 users, like this one. This may seem weird to outsiders, but instances like this one are one of the main draws of Mastodon.

> Are there filters between each server?

There _might_ be filters. Mastodon server admins can filter posts from certain foreign servers. For example the metalhead.club administrator chose to filter some instances which spam a lot or post extremist text and /or child pornography.

Often these filters are necessary for legal reasons, e.g. some jananese servers allow sketches of naked children ("loli"), which are considered child pornography in Germany and are therefore illegal in the server's home country.

I am very interested; I've been unable to find an instance with rules that are not involved in politics. What's that instance?