1. In Internet Explorer 4.0, submitting a form would only submit the 'innerText' content of the BUTTON (the text content of the element.)
  2. In Internet Explorer 5.0, submitting a form submits the contents of the VALUE attribute of the BUTTON if it is present. If it is not, the 'innerText' content of the BUTTON is submitted instead.

Button element with no value attribute:
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Button element with a value attribute set ("thebuttonvalue"):
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