Used in their formal question / answer sense, the meaning of a Q-code varies depending on whether the individual Q-code is sent as a question or an answer. For example, the message "QRP?" means "Shall I decrease transmitter power?", and a reply of "QRP" means "Yes, decrease your transmitter power", whereas an unprompted statement "QRP" means "Please decrease your transmitter power". This structured use of Q-codes is fairly rare and now mainly limited to amateur radio and military Morse code (CW) traffic networks.