Think of GSAP as the Swiss Army Knife of animation…but better. It animates anything JavaScript can touch (CSS properties, canvas library objects, SVG, generic objects, whatever) and it solves countless browser inconsistencies, all with blazing speed (up to 20x faster than jQuery), including automatic GPU-acceleration of transforms. See the http://greensock.com/why-gsap/ for details. Most other libraries only animate CSS properties. Plus, their sequencing abilities and runtime controls pale by comparison. Simply put, GSAP is the most robust high-performance animation library on the planet, which is probably why every major ad network excludes it from file size calculations and hosts it on their CDNs. Unlike monolithic frameworks that dictate how you structure your apps, GSAP completely flexible; sprinkle it wherever you want.