What is the Fediverse
The Fediverse is a kind of federation of different providers to enable a common data exchange.
What sounds very technical at first is explained by a simple and concrete example.
Services (Software)
The focus is on the services a user wants to use. E.g. a short message service. There is now the possibility to register with a service, if this is a closed service, only other members on this service can interact with one. One such service is Twitter. The same is true for other types such as video portals, music services, a.s.o.
Usually these services are closed source and are only provided by one provider.
Provider
Providers are these groups that provide one or more services. Since, as described, the services are often closed source, there is one provider for one service and the terms provider and service are virtually interchangeable.
Federated Services
A key focus for services in the Fediverse is the characteristic of being decentralized and federated.
That is, a piece of software is provided by multiple providers.
If these services speak the same technical language, they can communicate with each other.
A classic example is good old e-mail.
No matter with whom you have an account (own server, free account with a provider, something paid), everyone can communicate with everyone.
And it doesn't matter which email client is used (in principle, Outlook is the stupid exception).
Each provider can decide for themselves who can use the services and under what conditions.
Fediverse
Here it is analogous to e.g. email, but the difference is that there is an interface that allows different services to communicate with each other.
E.g. Mastodon (short message service), PeerTube (video platform), Pixelfed (Instagram alternative) and many more.
All these services can exchange data with each other and also for example Pixelfed can say someone uploaded a new video on PeerTube.
Or messages can be sent across services, or likes, comments, etc.
Most of these services are open source and can be set up and run by anyone with enough technical understanding.
According to the-federation.info, for example, there are currently nearly 3000 instances of Mastodon with over 2.8 million users, plus over 1000 Peertube instances with nearly 170,000 users, plus plus plus. All of them can exchange data with each other.
Content Nation, by the way, is also one of these services, though not yet with millions of users.
Unlike services with one provider, we now need two parts for unique association. A username and an instance.
So just like an email.
But so that this is not confused with an email and used similarly to other services, there is an @ in front of the name. So the profile here is for example. @help@contentnation.net , so @ username @ provider/instance.
Actually not complicated at all and so much more powerful than a single service provider. And if you don't like a provider, just use another one.