page_title: Radio button
section_title: Etymology
hierarchical_section_title: Radio button / Etymology
caption_attribution_description: Typical car radio of analog era. For Toyota's car, made by Fujitsu Ten.
context_page_description: A radio button or option button is a graphical control element that allows the user to choose only one of a predefined set of mutually exclusive options. The singular property of a radio button makes it distinct from a checkbox, which allows more than one item to be selected and for the unselected state to be restored.
  Radio buttons are arranged in groups of two or more and displayed on screen as, for example, a list of circular holes that can contain white space or a dot. Each radio button is normally accompanied by a label describing the choice that the radio button represents. The choices are mutually exclusive; when the user selects a radio button, any previously selected radio button in the same group becomes deselected. Selecting a radio button is done by clicking the mouse on the button, or the caption, or by using a keyboard shortcut.
  It is possible that initially none of the radio buttons in a group are selected. This unselected state cannot be restored by interacting with the radio button widget, though it may be possible through other user interface elements.
context_section_description: Radio buttons were named after the physical buttons used on older radios to select preset stations – when one of the buttons was pressed, other buttons would pop out, leaving the pressed button the only button in the "pushed in" position.
caption: A radio with a row of five pop-out buttons
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