title: How many arguments to setTimeout?
body: <p><a href="https://stackoverflow.com/a/3223466/765287">This SO answer</a> makes a call to <code>setTimeout</code> with four arguments.</p>
  
  <pre><code> setTimeout(self.process1, 0, self, u);
  </code></pre>
  
  <p>This confuses me.  The <a href="http://www.w3schools.com/js/js_timing.asp" rel="nofollow noreferrer">documentation</a> I've seen for <code>setTimeout</code> only uses two arguments, not four. </p>
  
  <p>What do the last two arguments do?  </p>