The Federation and You!


So recently there has been an influx of people joining Mastodon (or other federating services) after being banned from Twitter. There's a pretty big difference in the culture and functionality of these two services, so here are some of the things you should know.

The Fediverse

Mastodon is not a single website, it's part of a series of websites (called “instances”) that work together called the fediverse, sometimes shortened to “fedi.” Mastodon also isn't the only service out there. Others, like Pleroma and Misskey are also a part of the fediverse.

Users from instances running any of these services can connect to each other, so if someone you want to talk to is on a different instance or different service altogether, it doesn't matter too much. You'll still be able to like each others posts, reply to each other, etc.

Content Warnings

One of the biggest differences between the fediverse and Twitter is the usage of content warnings (or CWs). These are short descriptions of what's in your post that stick the main body of the post behind a button. Additionally, you can mark an image as sensitive if something in it might be uncomfortable for people. You should use your best judgement on this one, but here are some common things people may want tagged:

Generally nobody will get too mad if you slip up on tagging things every once in a while, but making it a habit can get you banned from your instance or, if your admin consistently doesn't take action against unruly users, get your instance defederated. If you have something you want tagged, most people are cool with you asking them to do so. It's not really that big a deal.

Federation & Defederation

The fediverse works through a process called federation. Sites in the fediverse send copies of their posts to each other, basically. It's a really complicated process to explain, but in practice it works seamlessly. The only major difference you'll notice between accounts on different instances is the domain name.

It works a bit like email addresses. If you username is “Gargron” and your instance is “”, someone would mention you in a post with ””. Mentioning someone will send them a notification, like you may expect.

Defederating is when two instances stop talking to each other. This can happen for any number of reasons. They could have conflicting rulesets, there could've been interpersonal drama, or the admins could just not like each other.

A big reason for defederation is not requiring users to tag NSFW posts, so make sure you're doing that. When an admin decides to defederate with an instance, they cut off communication with that instance entirely for their users. It's a serious decision and not taken lightly by admins of larger instances, but it's also not uncommon.


While the fediverse may feel similar to Twitter in a lot of ways, it's developed a culture with some different expectations. Knowing some of these expectations going in is an important part of making sure everybody has a good time. Here are some examples.

This list isn't exhaustive or a formal set of rules for any particular instance out there. Your instance might have more or less strict rules than these guidelines, so make sure to check things out lest you get in trouble with your local admin or worse.

Overall: Don't be a dick and don't be (too) weird. Remember that the person you're speaking to is in fact a person. Assume good faith and de-escalate the situation whenever possible if you get in an argument.

Privacy, Scopes, and Timelines

By design, nothing on the fediverse is truly private. This includes DMs. Because of the way federation works, data leaks are entirely possible and even common. Your admin can see anything you put on their instance. So can Twitter, for that matter, but your instance admin is also a member of the community here. Anything you put on the instance could potentially be seen by them. Same goes for cops. If you're plotting to overthrow the US government or something, you might want to do it somewhere more secure. “Scopes” are more of a guideline than a strict rule.

So scopes are something we haven't talked about too much yet, and they're one of the more notable distinctions between the fediverse and Twitter. The “scope” of a post is the group of people it's intended to be read by. The scopes available pretty universally are DM, followers-only, unlisted, and public.

DMs only go out to the people mentioned in the post, followers-only is self-explanatory, unlisted posts aren't on the local timeline (more on timelines in a bit), and public posts are viewable by anyone looking at the public or federated timelines. Some instances also support a “local-only” scope, meaning that it's only visible to users on the same instance. This isn't a default feature, but it's in the fairly popular Glitch-Soc variant of Mastodon so you may run into it at times.

There are multiple timelines on each instance and they're a good part of why you may pick one instance over another. They're as follows:

Your home timeline contains people you follow's posts and any posts mentioning you, the public timeline contains all the public posts made by people on your instance, and the federated timeline contains all the public posts your instance has a copy of no matter where they originated from. People on your public timeline will probably be a bit more immediately friendly than people on the federated timeline, but anyone on the federated timeline is at least generally cool with the audience of your instance.

Choosing an Instance

If you're still on board, it's time to choose an instance. The biggest general instance out there is, administered by Eugen Rochko, head of the Mastodon project. It's a popular starting place and doesn't defederate with too many other instances. Mastodon makes it easy to show that you've jumped instances, so don't worry too much about confusing your followers if you do.

If you don't want to use .social, there are a few good lists out there cataloguing instances. I'd recommend first and then for further exploring.

Look around and see what you like, but you've got a few things you should probably consider:

You're also able to host your own instance if you have the know-how, but I won't go into that in any detail here. If you're interested, Mastohost is a popular service for doing this. If you're hosting other people on your instance, you're accountable for their behavior. Don't host an open instance if you can't handle that.

Mobile Apps

For iOS, the big ones are Toot!, Mast, and Amaroq. The first two cost money but are much more to look at, Amaroq is free and no-frills but works pretty well all around. On Android, you've got Tusky, and Subway Tooter. I would avoid Tootdon and Pawoo. They have some morally questionable data collection practices. All of these should work on Mastodon and Pleroma both, although I'm not entirely sure about Misskey.

I'm an iOS guy myself and personally I use Amaroq, so I'd recommend that for a stable experience. I like Mast and Toot! a lot but I've had some crashes with Mast and Toot has some weird notification behavior. I haven't tried any of the Android apps myself.

Switching from any of these apps to any of the others won't require you to make any changes on your end, either. You can log in with the same accounts and it's not a big deal.

Other Fediverse Services

There are a handful of other services available outside of the big 3, like NextCloud, Peertube, Pixelfed, and WriteFreely. In fact, this blog federates. You can subscribe to it and it'll show up in your feed! There are all kinds of cool services that hook into your fediverse accounts, so check 'em out.

Peertube is for videos, Pixelfed is an Instagram and soon-to-be a Vine replacement, WriteFreely does blogs, and NextCloud is a whole bunch of stuff smashed together. It's one of the cooler aspects of the fediverse and something a lot of people forget about.

Closing Thoughts

If you're still reading, I hope you enjoy your stay in the fediverse. It's a unique and special place with some really great people in it. There's a learning curve, sure, but the people are helpful and, for me, it's been more than worth it.

Have fun,


PS: I'm putting this under a CC0 license. That means you can do what you want with it. Make derivatives, rehost it, whatever. No attribution needed, no linkbacks, nada. Do what thou wilt shall be the whole of the law.