title: What is the difference between $ and jQuery
body: <p>When I try to use <code>$("#div_id")</code> in <code>$(document).ready</code> it returns NULL, but when I use <code>jQuery("#div_id")</code> it returns the actual object!</p>
  
  <p>Why is that happening?</p>
  
  <p><strong>UPDATE:</strong> I tried noConflict method without gaining any hints.</p>
  
  <pre><code>jQuery.noConflict()
  function (a,b){return new c.fn.init(a,b)}
  
  $.noConflict();
  TypeError: Object function ()
      {
          return document.getElementById.apply(document, arguments)
      } has no method 'noConflict'
  </code></pre>
  
  <p>UPDATE 2:</p>
  
  <pre><code>$(document).ready(function() {
      debugger;
  });
  
  &lt;input type="text" id="test" name="test" value="123" /&gt;
  </code></pre>
  
  <p>When I run the following code in the console i got those results:</p>
  
  <pre><code>$("#test").val()
  TypeError: Cannot call method 'val' of null
  jQuery("#test").val()
  "123"
  </code></pre>
  
  <p>Thanks</p>