Modernizr is an open source and compact JavaScript library that allows developers to craft various levels of experiences for users with respect to cross-browser compatibility. Modernizr helps developers to perform cross-browser testing to check whether new the generation of HTML5 and CSS3 features are natively supported by their visitor’s browsers or not and to provide dedicated fallbacks for older browsers that are notorious for their poor feature support. Modernizr coupled with the principle of progressive enhancement helps to design cutting-edge websites layer by layer, taking advantage of powerful modern web technologies without discarding users that are still using older browsers like IE.
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