Why use Modernizr?
Taking advantage of the new capabilities of HTML5 and CSS3 can mean sacrificing control over the experience in older browsers. Modernizr 2 is your starting point for making the best websites and applications that work exactly right no matter what browser or device your visitors use.
Thanks to the new Media Query tests and built-in YepNope.js
micro-library as Modernizr.load(), you can now combine feature detection with media queries and conditional resource loading. That gives you the power and flexibility to optimize for every circumstance.