title: jQuery can't be accessed by other .js file
body: <p>Here is a html page:</p>
  
  <pre><code>    &lt;html&gt;
  &lt;head&gt;
      &lt;script src="http://code.jquery.com/jquery-1.9.0.min.js" type="text/javascript"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;script src="background.js" type="text/javascript"&gt;&lt;/script&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>Here is background.js:</p>
  
  <pre><code>alert("Alert1!");
  var test = jQuery.trim(" Words and / { objects &amp; things");
  alert("Alert2!");
  </code></pre>
  
  <p>Alert1 works, but alert2 never plays. If i remove the jQuery then it works.  I've tried the background.js file in both the header and body. What am I doing wrong?</p>
  
  <p>Thanks.</p>