A broadcast signal is a type of electromagnetic wave used to transmit audio and video content over the air. This signal is sent from a transmitter to a receiver, allowing people to access television and radio programs without needing a cable connection. The signal can be analog or digital, with digital signals providing better quality and more channels. Broadcast signals are typically transmitted from tall towers to cover large areas, ensuring that many people can receive the content. Devices like televisions and radios are equipped with tuners that can pick up these signals, enabling users to enjoy various channels and programs.