Radio

A single choice from a set, with every option visible at once. A group that shows its options instead of hiding them in a field.

Anotomy

Structure of the radio and how its internal parts are composed. These are the radio's semantic parts, so they are also what the classNames and styles objects accept. A button-style option from optionType="button" has the same three parts.
Radio anotomy
NameDescription
1rootThe <label> around the circle and the text, so a click anywhere on it selects the option. className lands here.
2iconThe circle, holding the real <input type="radio">. It draws the inner dot when the option is checked.
3labelThe text you pass as children, with the gap to the circle. It only renders when there are children.