Modernizr is a small piece of JavaScript code that automatically detects the availability of next-generation web technologies in your user's browsers. Rather than blacklisting entire ranges of browsers based on “UA sniffing,” Modernizr uses feature detection to allow you to easily tailor your user's experiences based on the actual capabilities of their browser. With this knowledge that Modernizr gives you, you can take advantage of these new features in the browsers that can render or utilize them, and still have easy and reliable means of controlling the situation for the browsers that cannot.