Is each instance like another person with a server?

Yeah. I would assume that most, if not all, open instances are going through a 3rd party hosting service, but nothing stopping them from being hosted on hardware in somebodies home.

Could that person just shut it down whenever they wanted to?

Yup. Anytime and for any reason. It might cause a moment of disruption, but the beauty of federation is that you can always setup an account on a new instance or create your own.

Are there any companies that have invested in hosting Lemmy/ other fediverse servers?

Yes. The only one I can think of off the top of my head is Facebook federating their Threads services. I'm sure that there are others.

Is each instance like another person with a server?

I just wanted to add, any computer with an internet connection can host a web page! A desktop, a laptop, anything. That's how the internet all started, as a collection on interconnected computers sharing data. I think many people nowadays forget this or even never knew about it (including me), since we live in a world where people spend all their time at like only a dozen websites. (Google, Instagram, Wikipedia...)

I have a public "webserver" in my basement. It's just some random computer hosting some photos for family members. And it's all completely free, I don't pay anything to do it. I could easily pop an instance of Lemmy on it too.

The biggest hurdles in setting up a server from home are needing some technical knowledge, and a free domain name / URL usually looks a little silly (unless you pay for one), and getting hacked is a very real threat unless you pay close attention to security.

If you created a Lemmy server, then you would be the owner of that particular instance, and yet another node in the fediverse. It's not owned by anyone, really. The entire point of activitypub is that it's entirely agnostic.

Is each instance like another person with a server?

Individual person, group of people, nonprofit, company, governments, political parties, whatever. Anything goes.

Could that person just shut it down whenever they wanted to?

Yes. That's why it's advisable to join one with a dedicated group of committed individuals, or run your own. Joining super small servers might sound nice, but the owners might just ditch it.

Are there any companies that have invested in hosting Lemmy/ other fediverse servers?

There are some run by companies, yes, for example social.bbc which is run by the British Broadcasting Corporation. gruene.social is run by the Greens (political party) in Germany, and social.overheid.nl is operated by the Dutch government.

There will probably be some company-run instances that don't allow user signup, since all they do is feredate with everyone and exfiltrate data. It's what people do...

Each instance is its own server/website but the servers talk to each other.
People and companies can both host their own instances though I am not aware of any servers owned by businesses.

If someone shut down an instance all the posts that have already been federated will still be on the other servers that instance has connected to but there will be no new posts.

The Fediverse in general does have instances owned by companies like how Mozzilla has its own Mastodon server.
I also think the Owners of wordpress also showed interest in the fediverse though I am not sure if they went anywhere with that.

This comment is an example of federation since I am from kbin.social but you are from lemmy.world yet I can see your post and comment on it.

The strength of the fediverse is that it's a whole network of individually owned servers. The weakness of the fediverse is that it's a whole network of individually ownwed servers.

it's a strength because you don't rely on large companies and are closer from the internet as it was designed with a decentralized network of equal importances server rather than a few big one. Which limits the power of the people owning the server and let having diverse moderation policies (e.g. I am all in letting a space for far righter mocking left-winter on Lemmygrad, but I am glad my instance doesn't federate with them)

It's a weakness, because the person running the instance may-close it tomorrow, many instance relies on someone spare ressources in time/infrastructure/money, some would accept donations,some are run by larger non profit (which also rely on donation, but have a legal structure to take them). It also means that they don't have the legal ressource to know the exact limit between legal and illegal leading to critic about their moderation closing community about topic like piracy Thread

the cool thing is that even if an instance closes, migration is fairly easy, so the impact is limited. It can be frustrating, I remember the closing of a large forum where I was involved in the large 00's which was quite frustrating for contributors (It was like a server crash followed by a corrupted backup, shit happens)

Note also that proprietary social media do close too, remember when google closed plus or wave ? or when yahoo close yahoogroups ? it's not like being owned by a large company means it'll be open forever (look at US trying to ban tik tok)

More than the developers of Lemmy, you're putting your trust in the instance owner/admin. Even if the site says "v0.19.3" at the bottom, there could be any code put in there by the server admin. This can be for better or worse, for example in lemm.ee the admin has frequently included code improvements that have made this instance more resilient than others. I'm not aware of any instance including malicious exploits, but in theory this would be possible. If one was caught doing this it would likely be defederated by others.

Is each instance like another person with a server?

Yes. However the instance admin and server admin might be different people. The server admin is probably also an instance admin, but some people might only be instance admin.

Could that person just shut it down whenever they wanted to?

Yes, the server admin has complete control. Instance admin have control within the instance, they can remove just about everything but they can't quite flip a switch and turn it off.

Are there any companies that have invested in hosting Lemmy/ other fediverse servers?

Facebook/Meta came in with Threads, but most instances refused to federate with them. I think the BBC also set up a Mastadon instance, they ran a trial which has either been extended or made permanent. There may be others, but the whole point of federation is that anyone can make an instance, be they private individuals or corporations. The big downside is that any instance then becomes another place to remove your content from - but really this is true of any website, which might be scraped by a 3rd party.

Is each instance like another person with a server?

Yes.

Could that person just shut it down whenever they wanted to?

Yes.

Are there any companies that have invested in hosting Lemmy/ other fediverse servers?

Idk, they'd be very niche.

Sorry I'm sure I messed up some of the terminology, I hope my questions make sense!

Nah, you pretty much nailed it.

Lemmy, and a lot of the fediverse, functions very similarly to email. Gmail can send emails to Proton even though they're hosted by two completely separate companies. A post/comment/vote/interaction is like an email in that a copy of every interaction is sent to every federated instance, like emails sent to recipients. This creates a lot of redundancy and traffic between instances, which has its pros and cons.

Why you do!

https://elest.io/open-source/lemmy

Or rather, we all do.

I hosted an instance during the rexxodus when I thought more people would come over and I used elest to host it. When it didn't catch on I moved over to world.

Some people also host a 'single person' instance so that they are in control of who they are federated with.

Users are like coffee drinkers and servers are like decentralized coffee shops that talk to each other ("federate"). Anyone can open a coffee shop and many do. It's harder and more expensive than simply drinking coffee, but not that bad in the scheme of things, and within reach of average hobbyists with time on their hands and a few bucks to spend.

If the instance stays small, it's cheap to run. If it gets popular, you can ask users for donations and volunteer help. Lemmy.world is the current biggest, and stays afloat that way.

Right now there's not much corporate presence, but that may change soon, unfortunately.

Could that person just shut it down whenever they wanted to?

it would mean shutting down that one particular instance only, all of the other instances would still be trucking along – whereas if the service-formerly-known-as-Twitter shuts down, everything on there is completely gone

in the case of Mastodon instances, if you get a heads-up that something is happening, you can migrate your account (and posts) to another instance – AFAIK that’s still in the works for Lemmy

each domain is hosted by individual groups. lemmy.world lemmy.ml sh.itjust.works individually managed and ran.

In simple terms, each individual server sends and receives content from all of the others and displays it to you. You can interact with lemmy.ml via lemmy.world, for example.

Any individual server could shutdown however content has been shared (federated) to other servers (instances) and stored so depending on content retention, it’s still available.

You can also run a server yourself.

Usually, servers are referred to as instances.

There are types in the fediverse, such as mastodon. Content is shared between them but displayed differently

In terms of commercial interest, facebook wants to eventually federate with their threads app.

Everything else is opensource and community funded, I believe

It would depend on the instance.

There's a lot of self-hosting enthusiasts here so I would assume at least some are owned by the instance admins themselves. But I would also guess some others use a 3rd party service and technically do not own the server they rent.

If I was to host my own instance, I would end up renting something because I don't have the UP speed to really run a webserver on my home internet. Nor the capacity on my one computer to handle any storage for people to do anything.