This script is the defacto way to enable use of HTML5 sectioning elements in legacy Internet Explorer.
A lightweight engine that allows you to hitch new capabilities to the browser (prollyfill).
Legacy support for the CSS3 Flexible Box Model
CSS4 parent selector based on jQuery
A fast & lightweight polyfill for min/max-width CSS3 Media Queries (for IE 6-8, and more)
Tired of adding prefix for each broswer when it comes to the new css3 attributes?
Tiny polyfill for the placeholder form element attribute. Requires Prototype.js.
A better way to use localStorage and sessionStorage
Allows for automatic Image fallbacks for browsers that can't handle SVGs
An Asynchronous Conditional Resource Loader
Small, fast, awesome. The only ES5-ish set of polyfills (shims) you can mix-and-match because they're individual AMD modules.