What does the term "OUT" mean in radio communication?

In radio communication, the term "OUT" indicates that the transmission is complete and no response is required from the recipient. This term effectively signals to the other party that they do not need to reply back, allowing for clear and concise communication. It helps prevent overcommunication and potential confusion, which is vital in situations where quick and precise exchanges are necessary, such as in train dispatching or emergency services. By using "OUT," the sender conveys that their message is finalized, ensuring that both parties are on the same page regarding the status of the conversation.