title: javascript node.js next()
body: <p>I see a lot of use <code>next</code> in node.js.</p>
  
  <p>What is it, where does it come from? What does it do? Can I use it client side?</p>
  
  <p>Sorry it's used for example here:
  <a href="http://dailyjs.com/2010/12/06/node-tutorial-5/">http://dailyjs.com/2010/12/06/node-tutorial-5/</a></p>
  
  <p>look for the loadUser function.</p>