The History of a Radio Button
"Radio Buttons"
A radio-button, AKA an "option button" is a UI element every web/mobile/desktop developer is familiar with. It allows choosing only one option out of a set.
Radio buttons are named after the actual physical buttons used on old radios to switch between frequencies and preset stations.
When a button was pressed, all other buttons would pop out, leaving the pressed button the only button in the "pushed down" state.
(Although in some radios, none of the buttons stayed "pushed in")
The UI concept has later been used in tape recorders, cassette recorders and wearable audio players (the famous "Walkman" and similar).
And later in VCRs and video cameras, all the way up to the early 90s - for the "play/pause/rewind/fast-forward" controls.
The GUI concept was first introduced by researches at Xerox PARC - an R&D company responsible for nearly every cool computer technology we use every day including: Ethernet, graphical user interface (GUI), object-oriented programming, computer mouse, laser printing, etc.
And the first device that featured a radio-button in its Graphical User Interface was Xerox Star 8010 workstation
...later adopted by Apple Lisa, Apple Macintosh, Atari ST, Commodore Amiga, Visi-On and Microsoft Windows
(in that order)