It‘s like Twitter basically, but since it‘s also in the fediverse there is a bit of overlap where Mastodon people can comment on Lemmy/kbin stuff too anyway. Usually they have something like @LostCause and hashtags like #mastodon and so on in their comments, that‘s how I typically spot them.
So their growth is relevant for us, but you don‘t need to make an account there.
If a mastodon user mentions (@) a community, they'll post there. They can also reply to comments on Lemmy and you'll see it. Unfortunately I don't think Lemmy has a way to see regular mastodon accounts/comments right now other than that.
Just like twitter except what you see on your feed is reliant on what #’s or people you follow. So you essentially have more control over what you see and you wont get any posts from some rando like twitter does
Mastodon is hard to get into because at first you only really see what is coming from your own instance. You have to really look around and find the people and topics you want to see in your feed. It's a much more carefully curated set of content than you get from Twitter, which just bombards you with hot takes and garbage all the time.
It's really interesting.. i gave it a shot a few days back. You've to follow stuff or hashtags you're interested in for things to show up.. after that take it slow and follow more things.. I've found some really good music playlists, art, programming discussions on there. There's also an explore section which shows trending topics and posts. I can recommend it as the users are mature and in my experience not toxic.
It's not like here at all. No shitposts. Only people who use their real name and work for some non profit sharing their highly intelligent news bulletins. I haven't found any memes