• Homework Solution
• .css()
• Callback Functions
• $.each()
• instanceof
• Homework Overview

//working with this element: //<div id='item'></div>//set a CSS style  var item = $('#item');  item.css('font-size', 24);//<div id='item' style="font-size:24px"></div>//get a CSS style  item.css('font-size');// > "24px"

• Because Functions are a first-class object in JavaScript, you can pass them as arguments into Functions. Then, they can be called at a later time.
• You can't just write code, you have to wrap it in a function declaration. This creates an anonymous function (because it has no name).
• A lot of jQuery uses callback functions.
• Perfect for asynchronous operations.
• Don't be afraid of them (they are your friend).
• Ryan, do a callback demo!

• Sort of a jQuery foreach.
• Pass an array or object as the first parameter.
• Pass a callback function as the second parameter.
• Callback function passes in the current index & value 

• Use instead of 'typeof', which is too generic.
• Tests for constructors on an objects prototype chain.
• Can be used for custom constructors.

 function constructObj() {}; var realObj = new constructObj(); realObj instanceof constructObj; // > true realObj instanceof Array; // > false realObj instanceof Object; // > true