javascript syntax dumb question
<p>I am very new to javascript, so I am baffled by the following syntax:</p>

<pre><code>if (isFunction(obj)){
  for (key in obj) {
    //do something
  }
 }
</code></pre>

<p>The isFunction method will return true if typeOf obj=="function". but what happens when you say key in obj?(when obj is a function?)
Thanks</p>
