Good question! Sometimes radios display other information too – like the name of the radio station and presenter or a phone in number.
Here’s how it’s done. Maybe you’ve downloaded music at home and listened to it from your tablet or laptop. The track gets turned into a packet of computer code which your music player knows how to read.
That’s a bit like what’s happening inside your radio. Radio stations have thousands of tracks on their computers – all in little packages of computer code.
The radio station will have a list of all the songs lined up to play and the times to play them. This information can be coded up alongside information about the station and instructions about how often they want the information to show on displays.
Radio waves are packets of energy which travel through the air. They are really handy because they can carry a lot of information with them. All the bundles of information are carried to your radio where the aerial is listening out for the station you have selected.
Your radio can decode the data carried by the radio waves to play the tune, and follow the instructions in the code to put the right images and words on the display at the right time!