When people hear the word "radio" they instantly think of commercial stations like Radio 1. However, as part of the ATC training one of the topics covered is "radios". This includes HF listening and UHF/VHF communicating.
Once the lighter months arrive we dig out the UHF portable radios and split into groups then go outside, venture off ino different directions, and test our communicating skills and techniques. This involves using the phonetic alphabet (for those of you that don't know what this is, yu may have heard police officers using it to read out car reigistration plates) e.g. Alpha India Romeo - Charlie Alpha Delta Echo Tango Sierra - this spells out AIR CADETS. We use radios during many different adventure-training activities and is a useful skill to have.
Once you have passed your initial radio test you can advance your skills by becoming a radio operator and so on until you gain your Communicators Badge - this being the highest level in the ATC.
If you find that you like using radios then you may even be interested in taking it up as a hobby and the ATC can help you gain your own call sign.