Just as cell phones, radio station online, GPS and satellite radio TV uses waves to operate.
Every grimerton radio station has a big antenna that acts as a transmitter. This is the antenna that sends waves with music or a DJ who speaks. It takes some super-antennas like this because online radio news must be transmitted far away.
Then, each device has a small antenna that acts as a receiver. It can be a small rod that comes out of the car (for radio), or it may be hidden (as in a cell). The receiver catches the waves and transmits music in speakers so that the sound is louder.
It’s a bit like baby monitors. There is a ‘micro’ in the House of the baby with a transmitter that sends waves and a small speaker with a receiver to hear what is happening!
Did you know there are a lot, a lot of radio waves which float in the air? To avoid that waves don’t “bump” …