JavaScript change content demo

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
  <title>JavaScript change content demo</title>
</head>
<body>
  <h1>Blink and you'll miss it...</h1>
  <p id="demo">This is a paragraph.</p>
  <script type="text/javascript">
  <!--
  document.getElementById("demo").innerHTML=Date();
  //-->
  </script>
</body>
</html>