My Photoshop Classroom

Today we’ll discuss how to improve the paint performance of your websites and Web apps. This is an area that we Web developers have only recently started looking at more closely, and it’s important because it could have an impact on your user engagement and user experience.

Frame Rate Applies To The Web, Too
Frame rate is the rate at which a device produces consecutive images to the screen. A low frames per second (FPS) means that individual frames can be made out by the eye. A high FPS gives users a more responsive feel. You’re probably used to this concept from the world of gaming, but it applies to the Web, too.
Long image decoding, unnecessary image resizing, heavy animation and data processing can all lead to dropped frames, which reduces the frame rate, resulting in janky pages. We’ll explain what exactly we mean by “jank” shortly.



Source: http://www.smashingmagazine.com/2013/06/10/pinterest-paint-performance-case-study/