<input type="radio"> defines a radio button.
Radio buttons let a user select ONE of a limited number of choices:
Example
<form>
<input type="radio" name="gender" value="male" checked> Male<br>
<input type="radio" name="gender" value="female"> Female<br>
<input type="radio" name="gender" value="other"> Other
</form>
This is how the HTML code above will be displayed in a browser:
MaleFemale
Other
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