Client side validation with HTML and without JavaScript

To display HTML5 client-side validation error bubbles, use the required attribute.

You do not need to have javascript for client side validations like empty text box would never be submitted because HTML5 introduced a new attribute called required which would be used as follows and would insist to have a value:

      <form action = "/cgi-bin/html5.cgi" method = "get">
         Enter email : <input type="text" name = "newinput" required/>
         <p>Try to submit using Submit button</p>
         <input type = "submit" value = "submit" />