A radio is an electronic device used to receive and transmit sound through radio waves. It works by capturing invisible electromagnetic waves sent from a broadcasting station and converting them into audible sound. Radios are commonly used for listening to music, news, weather reports, sports updates, and other programs. They can be powered by batteries, electricity, or rechargeable sources. Radios may come in different forms such as portable radios, car radios, or built-in home systems. It is one of the earliest and most important inventions in communication technology, allowing information to reach people quickly over long distances without wires.