title: receiving data in php through jquery ajax
body: <p>i just got the hang of using jquery ajax 
  for example, this code sends the contents of the comment box to the php file.</p>
  
  <pre><code>    $.post("user_submit.php", {
        comment: $("#comment").text()
      });
  </code></pre>
  
  <p>the question however is how do i receive the data in the user_submit.php file?</p>