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copied!<ol> <li><p>The <code>new</code> keyword creates an instance of your <code>Console</code> object which you can then call the <code>Log</code> method on. If you just call <code>Console()</code> directly, you'll get whatever the return value is for that function. In your case there is none, so <b><code>undefined</code></b>. Additionally, if you don't use the <code>new</code> keyword, anything you assign to <code>this</code> within that "class function" will pollute the global scope. So instead of assigning your methods to <code>this</code>, you'd have to use a <b>proxy object</b> which you would return instead.</p></li> <li><p>In your example you're assigning the <code>logger</code> variable to the <b>return value</b> of calling your anonymous function. Again, it doesn't return anything so calling <code>new logger()</code> won't work because you can't instantiate <code>undefined</code>. So, removing the trailing <code>()</code> from the anonymous function will assign the <b>function</b> to <code>logger</code> rather than its return value, which you can then instantiate with <code>new</code>. (You could also use a proxy object again).</p></li> </ol> <p>In both the above examples, I'd strongly advise using the <b><code>new</code> keyword</b> rather than creating and returning a proxy object. This takes advantage of Javascript's built in instantiation mechanism and the function prototype chain, and is <b>much faster</b> than object creation.</p> <p>This blog post by John Resig is worth a read for more information on how "class" instantiation works in Javascript: <a href="http://ejohn.org/blog/simple-class-instantiation/" rel="nofollow noreferrer">http://ejohn.org/blog/simple-class-instantiation/</a></p>

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