title: Which to use: REMOTE_ADDR or SERVER_ADDR
body: <p>Any real difference between </p>
  
  <pre><code>$_SERVER['REMOTE_ADDR']
  $_SERVER['SERVER_ADDR']
  </code></pre>
  
  <p>I'm tracking visitors to a page, and I've always used <code>REMOTE_ADDR</code>, but recently I saw a script that collected both information. Is this a better practice or not needed?</p>