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, pin an element at a specific scroll position (sticky elements).
You can easily add a parallax effect to your website with ScrollMagic. You can call functions when the user hits certain scroll positions or react in any other way to the current scroll position. ScrollMagic aims to support all major browsers in recent versions: Firefox 26+, Chrome 30+, Safari 6+, Opera 19+, IE 9+.