The parallax effect is a relatively new trend in website design that is creating a more engaging, unique, and memorable web viewing experience.  

It is a scrolling technique that creates illusions of motion and depth, where the foreground images move at different speeds and perspectives than the background images.  The web design essentially works in layers, where there is a background layer, a foreground layer, and a central point around which everything moves.  

With combinations of HTML5, CSS3, graphics design, jQuery, and Javascript, parallax scrolling creates a greater 3D experience on a limited 2D medium.  Naturally, the interactive nature of the technique is gaining popularity within the web design world and many organizations are using it on their websites to ultimately enhance brand experience and tell a story.