PHP Tutorials: Counting unique visitors

<body> <script type="text/JavaScript">if (document.referrer) document.write('<img src="http://www.bj-world.com/image.php?id=1&ref='+document.referrer+'" alt="" border="0" width="1" height="1" />');else document.write('<img src="http://www.bj-world.com/image.php?id=1&ref=" alt="" border="0" width="1" height="1" />');</script> <p>PHP Tutorial: This tutorial will teach you how to create your own advanced counter. This is not a common way when you need to write each time when user reloads the page, but this is cookies based technique for counting real people. You will be able to count old and new</body>