For example, they had a channel named 'Gossip', and you could talk on it with the command 'Gossip <message>, but if you merely typed 'Gossip', it would show you the last ten messages that went through that channel.
For example:
GOSSIP
--- GOSSIPS ---
[Moonglum >> humanic]
"hello all"
[A male human >> humanic]
"hello"
[Moonglum >> humanic]
"what kind of amphibian?"
[A male human >> humanic]
"best one"
[A silver-haired elf with piercing blue eyes >> ???]
"shield vendor at med fount...for now."
[A silver-haired elf with piercing blue eyes >> ???]
"come and get them"
Why is this realistic? In role-play terms, even if you the player just connected, your character was always there (not logged out then he logged back in). He had his pendant on, and he heard the esp channel, so he is able to respond to messages on the ESP channel.