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copied!<p>Yes, the first function has no relationship with an object instance of that <a href="https://developer.mozilla.org/en/Core_JavaScript_1.5_Guide/Creating_New_Objects/Using_a_Constructor_Function" rel="noreferrer">constructor function</a>, you can consider it like a <em>'static method'</em>.</p> <p>In JavaScript functions are <a href="http://en.wikipedia.org/wiki/First-class_function" rel="noreferrer"><em>first-class</em></a> objects, that means you can treat them just like any object, in this case, you are only adding a property to the <em>function object</em>.</p> <p>The second function, as you are extending the constructor function prototype, it will be available to all the object instances created with the <a href="https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Operators/Special_Operators/new_Operator" rel="noreferrer"><code>new</code></a> keyword, and the context within that function (the <a href="https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Operators/Special_Operators/this_Operator" rel="noreferrer"><code>this</code></a> keyword) will refer to the actual object instance where you call it.</p> <p>Consider this example:</p> <pre><code>// constructor function function MyClass () { var privateVariable; // private member only available within the constructor fn this.privilegedMethod = function () { // it can access private members //.. }; } // A 'static method', it's just like a normal function // it has no relation with any 'MyClass' object instance MyClass.staticMethod = function () {}; MyClass.prototype.publicMethod = function () { // the 'this' keyword refers to the object instance // you can access only 'privileged' and 'public' members }; var myObj = new MyClass(); // new object instance myObj.publicMethod(); MyClass.staticMethod(); </code></pre>

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