It's the underlying protocol that connects the various federated services in the "Fediverse", (see https://en.wikipedia.org/wiki/Fediverse) like Mastodon, PeerTube, NextCloud, etc. At root it's just a standardized way for nodes in a network to send messages to each other, though, so you could use it to get those "connections of a social network" you're looking for. And then Mastodon users, say, could get updates/notifications from your site/service/whatever right in their feed.
It's the underlying protocol that connects the various federated services in the "Fediverse", (see https://en.wikipedia.org/wiki/Fediverse) like Mastodon, PeerTube, NextCloud, etc. At root it's just a standardized way for nodes in a network to send messages to each other, though, so you could use it to get those "connections of a social network" you're looking for. And then Mastodon users, say, could get updates/notifications from your site/service/whatever right in their feed.