The ActivityPub protocol is a decentralized social networking protocol.
In ActivityPub, a user is represented by “ actors” via the user’s accounts on servers. User’s accounts on different servers correspond to different actors.
Based on ActivityStreams, a social data syntax.
Each actor has:
inbox: How they get messages from the world
outbox: How they send messages to others
Here’s how sending and reading messages work
- You can POST to someone’s inbox to send them a message (server-to-server / federation only… this is federation!)
- You can GET from your inbox to read your latest messages (client-to-server; this is like reading your social network stream)
- You can POST to your outbox to send messages to the world (client-to-server)
- You can GET from someone’s outbox to see what messages they’ve posted (or at least the ones you’re authorized to see). (client-to-server and/or server-to-server)
Messages made by clients get posted to their own server’s outbox and the server then posts that to the receiver’s inbox.