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    <h2>Function vs Object declaration</h2> <p>You can't use that particular syntax, the correct form is:</p> <pre><code>var myFuncs = { firstFn: function () {}, secondFn: function () {}, ... }; </code></pre> <p>The advantage to writing functions within an object has to do with namespacing and context. If you wrote:</p> <pre><code>var firstFn = function () {}; -or- function firstFn() {} </code></pre> <p>the function would be defined at <code>window.firstFn</code>. Adding the functions on <code>myFuncs</code> makes the functions accessible at <code>window.myFuncs.firstFn</code>. If you want your JavaScript to work with other scripts you wouldn't want to have your <code>foo</code> function conflict with someone elses <code>foo</code> function:</p> <pre><code>&lt;script src="a.js"&gt; function foo() {...} &lt;/script&gt; &lt;script src="b.js"&gt; function foo() {...} //this script would overwrite the foo function in a.js &lt;/script&gt; &lt;script src="c.js"&gt; var bar = { //this script would be accessed at bar.foo() foo: function () {..} } &lt;/script&gt; </code></pre> <p>The calling context (<code>this</code>) of the function will also be different:</p> <pre><code>function foo() { console.log(this); //window } var bar = { foo: function () { console.log(this); //bar object } } </code></pre> <hr> <h2>Closure Syntax</h2> <p>What you may be getting confused with is the syntax for declaring functions within a closure:</p> <pre><code>(function () { var foo = function () {...}; foo(); }()); </code></pre> <p>In this case the closure is used to prevent the function from polluting the global scope (<code>window.foo</code> will not be set). This allows multiple scripts to use the same function names without worrying about being overridden.</p> <hr> <h2>OOP Syntax</h2> <p>The object syntax is often used to define the prototype for a JavaScript "constructor". In JS all functions can be called as a constructor simply by using the <code>new</code> keyword when the function is called:</p> <pre><code>function foo() {...} var f = new foo(); //don't do it this way </code></pre> <p>For readability/maintainability/consistency you should always name your constructor using PascalCase:</p> <pre><code>function Foo() {...} //tells other developers this is a constructor function bar() {...} //tells other developers this is a function var f = new Foo(); var b = bar(); </code></pre> <p>Without getting too lost in the details of how prototype works, you can assign methods to be shared across every instantiated object of a function by assigning an object to the function's <code>prototype</code> property:</p> <pre><code>function Foo() {...} Foo.prototype = { //note the use of the object declaration for the functions bar: function () {...}, baz: function () {...}, ... }; var f = new Foo(); f.bar(); //calls the bar function that was defined in the prototype </code></pre>
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    1. COthanks. so in your opinion it is better "practice" to write within objects for my web application ? i.e. is better in the sense that it allows you to specifically declare myFuncs.firstFun(); which restricts the global scope - while probably making it easier to read ? i.e. account.settings(); etc ?
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    2. COStart with writing your functions within a closure. If they're needed outside the closure, set them explicitly on the global object (i.e. `window.foo = foo`). Within the closure, if you have a need of Object Oriented JavaScript, declare some constructors and set the functions on the `prototype`.
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    3. COthanks so much for the response :) clear now! awesome!
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