# POP3 Post Office Protocol 3 (POP3) commands: - USER - Username to use for authentication - PASS - Password to use for authentication - STAT - Mailbox statistics (`+OK $TOTAL_MSGS $MBOX_SIZE_BYTES`) - LIST - List messages (`$MSG_NUMBER $MSG_SIZE_BYTES`) - RETR - Retrieve message `$MESSAGE_NUMBER` - QUIT - Close connection There are other commands, but the above are enough to pull messages.