ScrollMagic is a jQuery plugin which essentially lets you use the scrollbar like a progress bar.It’s the plugin for you, if you want to start an animation at a specific scroll position, synchronize an animation to the scrollbar movement, easily add a parallax effect to your website, pin an element at a specific scroll position.
Features:
optimized performance
flexibility
mobile compatibility
ready for responsive webdesign
object oriented programming and object chaining
event management
support for both scroll directions (even different on one page)
support for scrolling inside div containers (even multiple on one page)
