Supabase provides a globally distributed cluster of Realtime servers that enable the following functionality:

  • Broadcast: Send ephemeral messages from client to clients with low latency.
  • Presence: Track and synchronize shared state between clients.
  • Postgres Changes: Listen to Postgres database changes and send them to authorized clients.

A channel is the basic building block of Realtime and narrows the scope of data flow to subscribed clients. You can think of a channel as a chatroom where participants are able to see who's online and send and receive messages; similar to a Discord or Slack channel.

All clients can connect to a channel and take advantage of the built-in features, Broadcast and Presence, while extensions, like Postgres Changes, must be enabled prior to use.

See Also#