Due to recent news, I have moved over (partially) my social media time to the Fediverse. But what is it?
The fediverse (a portmanteau of "federation" and "universe") is an ensemble of federated (i.e. interconnected) servers that are used for web publishing (i.e. social networking, microblogging, blogging, or websites) and file hosting, but which, while independently hosted, can communicate with each other. 
This was taken off wikipedia but I think does the job of describing what the Fediverse is.
Back in 2008, a social network called 'indeti.ca' was founded and published under the GNU Affero General Public License (AGPL). There was only a few instances (a self hosted 'website' in which users can sign up to) but the idea people loved.
The idea grew and in 2018, the W3C presented the 'ActivityPub' protocol. The aim of this was to improve interoperability between platforms. Many of the platforms have adopted this and thrive because of it.
It harps back to a time long forgotten (i dunno i wasn't alive lol).
You can find more about the platforms I am going to talk about here (such as apps, instances, FAQ)
Due to the nature of having multiple self-hosted instances, you can access the fediverse from a multitude of platforms dotted around the internet! The protocols used in these instances are simple and more often than not cross platform!
This is arguably the most popular piece of software. Mastodon is a FOSS self-hosted instance which functions similar to Twitter. The way the software works is:
You can start from any instance you want. This is intended to give users the flexibility to select a server whose policies they prefer whilst also keeping integrated with the wider world. No one person runs the fediverse.
You may use the site like Twitter, however it is not the same. There is no algorithm to please. All toots are in chronological order, you gain nothing from having more follows, there is no ads, no tracking and thankfully no overlord running the site because he's evil and wanted to spend an ungodly amount on it.
Don't expect to be flooded with lots of content to enjoy. The idea of Mastodon isn't to please and entertain you (there is no benefit in that). It's used more for microblogging, following projects and interacting with like minded people. There is many bots on this site that cross-post Twitter tweets as well! You may stumble across Pleroma instance-based toots as well, this is another federated platform.
I prefer this way because it massively reduces the time I spend on social media anyway. The mental health effect of social media is horrendous.
You can follow me on there! Join ANY instance (which you like, I recommend @mastodon.social if you aren't techy) and search for @email@example.com!
(Fun fact: the day Musk bought twitter, 30,000 new users had joined Mastodon! We are now at nearly 100,000 new users in two weeks!)
mastodon.org/ Join Mastodon today!
Peertube is a FOSS decentralised federated video platform whose back-end relies on the ActivityPub and WebTorrent software. It uses peer-to-peer technology to reduce load on individual instances. The aim is to provide a FOSS alternative to YouTube. Many YouTuber's either cross-post or only post on this platform.
Pixelfed is a new addition to the fediverse. This is a photo-sharing social media akin to Instagram. Much like Mastodon, this is a self-hosted platform in which users can post images, follow people, like and comment on posts as you would on Instagram. I can't say much on the matter as I haven't interacted much with it but the idea I just love!
This is a social network that allows the users to track, talk and discover all matters of books! I may start an account on this! As you can see, this is made to replace Goodreads!