What word is used to signify that a message was received and understood?

The term "ROGER" is commonly used in radio communications to indicate that a message has been received and understood. This terminology is derived from the phonetic alphabet, where "Roger" specifically signifies "R," meaning "received." Using this term helps maintain clarity and ensures that all parties in communication are on the same page, especially in situations where miscommunication could lead to safety issues.

In contrast, alternatives like "OVER" or "RECEIVED" might not be as universally recognized or clear in terms of indicating complete understanding. "ACKNOWLEDGED" could also be used, but it lacks the specific ties to radio protocol that make "ROGER" the standardized choice in many formal communication settings. Overall, "ROGER" serves to eliminate ambiguity, which is crucial in operational contexts like those encountered by a SEPTA Assistant Conductor.