Radio call signs are unique identifiers assigned to radio stations, aircraft, ships, and other communication entities. They help distinguish one transmitter from another, ensuring clear communication, especially in crowded airwaves. Call signs can consist of letters and numbers, often reflecting the location or purpose of the entity, such as airlines using specific codes for their flights. In aviation, for example, a commercial flight might have a call sign that combines the airline's name with the flight number, like Delta Air Lines flight 123 becoming "Delta 123." This system enhances safety and efficiency in communication, allowing for quick identification and response in various situations.