Is some thing wrong in this jquery code
<p>Hi I have become total mad on finding problem with this code</p>

<pre><code>  $(document).ready(function() {

        $("#centCol").hide();
        var isBrand = $('#merchantOption', window.parent.document).val();
        var shopType = '&lt;?php echo $this-&gt;shopDetail['shop_type']; ?&gt;';
        if(isBrand == '1' &amp;&amp; shopType != '4' &amp;&amp; shopType != '10'){
            $('#menu').hide();
        }
    });
</code></pre>

<p>When I run this code it gives me an error</p>

<blockquote>
  <p>$ is not defined $(document).ready(function() {</p>
</blockquote>

<p>I have even tried by changing <code>$</code> with <code>jQuery</code> but nothing done. One thing that make me more mad that When this code is online there is no error...... Can any body tell me what the heck of this?</p>

<p><strong>UPDATED</strong></p>

<p>My head section looks like this</p>

<pre><code> &lt;head&gt;
    &lt;meta http-equiv="Content-Type" content="text/html; charset=utf-8" /&gt;
    &lt;title&gt;&lt;/title&gt;                &lt;link rel="icon" type="image/x-icon"  href="/application_data/frontend/images/wlm-favicon.ico" /&gt;
    &lt;link href="/application_data/css/structure-styles.css" rel="stylesheet" type="text/css" /&gt;
    &lt;link href="/application_data/css/linkshare-color-style.css" rel="stylesheet" type="text/css" /&gt;
    &lt;link href="/application_data/css/colorbox.css" rel="stylesheet" type="text/css" /&gt;
    &lt;script type="text/javascript" language="javascript" src="/application_data/js/jquery.min.js"&gt;&lt;/script&gt;        
    &lt;script type="text/javascript" language="javascript" src="/application_data/js/jquery.colorbox-min.js"&gt;&lt;/script&gt;

    &lt;script type="text/javascript" language="javascript" src="/application_data/froomerce-frontend/js/common.js"&gt;&lt;/script&gt;
                &lt;script type="text/javascript" language="javascript" src="/application_data/ras-front/js/jquery-ui.js"&gt;&lt;/script&gt;
        &lt;script type="text/javascript" language="javascript" src="/application_data/frontend/js/jquery.jcarousel.min.js"&gt;&lt;/script&gt;
        &lt;script type="text/javascript" language="javascript" src="/application_data/js/jquery.flot.min.js"&gt;&lt;/script&gt;
        &lt;script type="text/javascript" src="/application_data/uploadify/swfobject.js"&gt;&lt;/script&gt;
        &lt;script type="text/javascript" src="/application_data/uploadify/jquery.uploadify.js"&gt;&lt;/script&gt;

        &lt;link href="/application_data/frontend/css/jquery-ui.css" rel="stylesheet" type="text/css" /&gt;
        &lt;link href="/application_data/frontend/css/skin.css" rel="stylesheet" type="text/css" /&gt;

    &lt;script type="text/javascript"&gt;
        opacity = '0.7';
        $(document).ready(function(){
            $(".network").colorbox({width:"560px", height:"348px", iframe:true, opacity:opacity,onClosed:function(){ window.location.reload( false );}});
            $(".addWidget").colorbox({width:"860px", height:"890px", iframe:true, opacity:opacity,onClosed:function(){window.location='/widget/index/list';}});
            $(".postOnPage").colorbox({width:"525px", height:"700px", iframe:true, opacity:opacity});
            $(".embedcode").colorbox({width:"620px", height:"400px", iframe:true, opacity:opacity});
        });
    &lt;/script&gt;
&lt;/head&gt;
</code></pre>
