title: Is HTML5 Web Workers for a page or across pages
body: <p>I went through couple of articles that talk about Web Workers in HTML5 and I was not able to clearly understand the following:</p>
  
  <ul>
  <li>Is the life cycle for a web worker limited to a single page or across pages of an domain?</li>
  <li>Is the life cycle for a web worker persistant after a page is loaded?</li>
  <li>Are web workers a better option to using than an ajax call within setInterval?</li>
  </ul>
  
  <p>Appreciate if someone could help me shed some light on the above questions.</p>