JavaScript for...in vs for
<p>Do you think there is a big difference in for...in and for loops? What kind of "for" do you prefer to use and why?</p>

<p>Let's say we have an array of associative arrays:</p>

<pre><code>var myArray = [{'key': 'value'}, {'key': 'value1'}];
</code></pre>

<p>So we can iterate:</p>

<pre><code>for (var i = 0; i &lt; myArray.length; i++)
</code></pre>

<p>And:</p>

<pre><code>for (var i in myArray)
</code></pre>

<p>I don't see a big difference. Are there any performance issues?</p>
