How to make a referral system?
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/5850962/how-to-count-clicks-on-a-get-value-with-php">How to count clicks on a $_GET value with php?</a>  </p>
</blockquote>



<p>I would like to create a referral system in which every new visitor gets his own unique link like <a href="http://example.com/?ref=12345" rel="nofollow">http://example.com/?ref=12345</a>. Does anyone know how this can be done?</p>
