The w3 explanation of form action attribute is it specifies where to send the form-data when a form is submitted ( http://www.w3schools.com/jsref/prop_form_action.asp ).
I have a simple javascript widget that calculates something and displayes the result in a designated table cell in the the same page. I have a line
<form name="form1" action="">
which works, but w3 code validator for html5 says I can't leave action blank. When I put the url of my page into action it does work, but I am not sure if that's what is indeed supposed to be there. I realize it is not so critical to pass the validator, but I still wonder what is the proper entry into form action if the result is in the same page?