rich1.0dtonon (npub100…8vwqk)https://yabu.me/npub10000003zmk89narqpczy4ff6rnuht2wu05na7kpnh3mak7z2tqzsv8vwqknjumphttps://yabu.meWhat you mean with "a channel"? You send your post to one or more relay, other clients subscribe to these relays and so be notified by new content. If two user don't share a common relay is possibile that they cannot read each other. Check https://nostr.how for a introduction to Nostr.