The frame rate, the speed the animation is played at, is measured in number of frames per second (fps). A frame rate that’s too slow makes the animation appear to stop and start; a frame rate that’s too fast blurs the details of the animation. A frame rate of 12 fps usually gives the best results on the web. QuickTime and AVI movies generally have a frame rate of 12 fps, while the standard motion‑picture rate is 24 fps.

The complexity of the animation and the speed of the computer the animation is being played on affect the smoothness of the playback. To determine optimum frame rates, test your animations on a variety of machines.

Because you specify only one frame rate for the entire Flash document, set this rate before you begin creating animation.