(Last update 17 February 2021)
Facebook, Twitter, and YouTube are engaging in rampant political censorship. The Fediverse is a decentralized, privacy-respecting, FOSS alternative to these Big Tech platforms. If you can't quite wrap your head around what it is or why it's a better solution than centralized "free-speech" platforms like Gab, Minds, Parler, and BitChute, the following videos do a good job of explaining it:
The Fediverse isn't necessarily an oasis of free speech. Some instances censor. The purpose of this page is to list those that don't.
Mastodon and Pleroma resemble Twitter.
PeerTube is like YouTube but uses P2P technology.
SearX is a decentralized, privacy-respecting, FOSS metasearch engine. It isn't part of the Fediverse but doesn't seem out of place on this page. Since reliable public instances can take some effort to find, I've listed a few below: