O.K. I always wondered why radio buttons were called that. I guess I didn't think about the software developers remembering (or being old enough to remember) when radios were operated by the pushbuttons.
I remember them well. You pulled them part way out and then pushed them all the way in to set your presets for your radio stations.
I'll remember reading this article the next I'm filling out a form online that the "radio" buttons are the ones that present an either/or choice. That's a good way to remember how they function. When you’re old enough to remember pushbutton radios, little memory aids are a good thing.