Both involve transmitting data through radio signals.
Explanation:
WiFi works on a rather high frequency compared to traditional radio. The higher frequency of Wifi makes it ideal for short range data transfer. There is a lot of bandwidth for data, but it's short ranged.
Radio waves are on a much lower frequency compared to WiFi. The lower frequency of radio makes it ideal for long range simple data transfer. This means only basic things can be transmitted, like voice. It would not be ideal for browsing the internet, loading images, watching videos, etc.
