The value attribute of checkboxes in HTML

 Use the Value Attribute With Radio buttons and Checkboxes:

• When a form gets submitted the data is sent to the server and includes entries for the options selected.
• Inputs of type radio and checkbox report their values from the value attribute.
• For example:

<label for="indoor">
  <input id="indoor" value="indoor" type="radio" name="indoor-outdoor">Indoor
</label>
<label for="outdoor">
  <input id="outdoor" value="outdoor" type="radio" name="indoor-outdoor">Outdoor
</label>

• Here you have two radio inputs.
• When the user submits the form with the indoor option selected, the form data will include the line: indoor-outdoor = indoor.
• This is from the name and value attribute of the "indoor" input.
• If you omit the value attribute, the submitted form data uses the default value.
• IN this scenario if the user clicked the "indoor" option and submitted the form, the resulting form data would be indoor-outdoor = on, which is not useful.
• So the value attribute needs to be set to something to identify the option.