Higher priced radios can remember the setup for several different models. Not every truck , plane, boat whatever have the exact same servo movements and centering trim. If Iwas to try and use one radio in a different model the steering might be reversed or it may track to the left or something. So radio manufacturers have included computers in the radio that you can choose the model , assign it a number and it will remember that model number 3 has the steering reversed for example, you just choose that model number for the correct model you want to run .
Ihave 19 airplanes, my new Hitec Optic6 radio can remember 10 different ones so Idont need 19 radios, just 2.