title: mainframe in Joomla
body: <p>The <a href="http://help.joomla.org/content/view/773/125/" rel="nofollow noreferrer">hello world tutorial</a> for Joomla states:</p>
  
  <blockquote>
    <p>$mainframe is a global variable in
    Joomla that has lots of useful methods
    attached to it.</p>
  </blockquote>
  
  <p>How do I find out what these methods are? I tried searching through their documentation, but I couldn't find any clues.</p>