title: JQuery source code questions
body: <p>I got two questions about following code snippet.</p>
  
  <p>(1). What is the purpose of "return new jQuery.fn.init( selector, context, rootjQuery );"? Why does it return another instance inside the JQuery function?</p>
  
  <p>(2). Why prototype.constructor is re-defined as JQuery?</p>
  
  <pre><code>// Define a local copy of jQuery
  var jQuery = function( selector, context ) {
          // The jQuery object is actually just the init constructor 'enhanced'
          return new jQuery.fn.init( selector, context, rootjQuery );
      },
  
  ... ...
  
  jQuery.fn = jQuery.prototype = {
      constructor: jQuery,
      init: function( selector, context, rootjQuery ) {
          var match, elem, ret, doc;
  </code></pre>
  
  <p>Thank you!</p>