@docpop I think I'd start with a point that "it's a social media network owned (operated, paid for, hosted, governed and moderated) by the society in it".

This can pivot into a number of questions depending on what the asker is most interested in, which is probably the only way to explain something as complex at Fedi:
- how are popular networks free (ads and associated conflicts of interest)
- why hosting matters (sustainability)
- is moderation ok (Facebook's certainly isn't, here it at least varies, if both ways)
- what can it do that popular networks can't (can't sub to a YouTube channel from Twitter, but can to a PeerTube channel from Mastodon; having rules that are not in line with {their favorite platform}'s ToS)
- why does this even matter (tremendous power over societies enforced by recommendation algos and content policies)