title: How to get all client info from website visitors?
body: <p>I want to collect all the information that we could when someone is visiting a webpage: e.g.:</p>
  
  <pre><code>clients screen resolution: &lt;script type='text/javascript'&gt;document.write(screen.width+'x'+screen.height); &lt;/script&gt;
  referer: &lt;?php print ($_SERVER['HTTP_REFERER']); ?&gt;
  client ip: &lt;?php print ($_SERVER['REMOTE_ADDR']); ?&gt;
  user agent:  &lt;?php print ($_SERVER['HTTP_USER_AGENT']); ?&gt;
  </code></pre>
  
  <p>what else is there?</p>