The Fediverse
Platforms
Mastodon
Mastodon is a Free (as in freedom) and Open Source (FOSS) microblogging platform that offers an alternative to the coporately owned and ad / data mining-supported platform called Twitter.
Searchable list of Mastodon instances to join
Friendica
I just signed up for an account on Friendica (Dec 2022). As opposed to Mastodon, Friendica is positioned to be a Facebook replacement; its interface resembles an older version of FB, but is still pretty functional. Currently there are quite a few more users on Mastodon than there are on Friendica, but the familiar interface may attract FB / Twitter "refugees".
Pleroma
Alternative to Mastodon. Much more lightweight, and can be hosted on a Raspberry Pi or a cheap VPS (for self hosting). Has some different user interfaces and options that Mastodon doesn't have.
Funkwhale
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Peertube
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Pixelfed
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Writefreely
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Misskey
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Bookwyrm
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Lemmy
Lemmy is a Free (as in freedom) and Open Source (FOSS) alternative to Reddit. They are part of the Fediverse but they focus on groups and topics instead of people. I haven't tried it, but you can apparently (or will be able to) follow people (not groups or topics) from other ActivityPub projects like Masto or Pleroma.
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