The animation above doesn't really demand layer-based editing. But imagine a few more layers and a lot more objects. This lets you use programming techniques to control animation. You can loop an animation as long as a particular condition exists or for a particular number of repetitions. Shared libraries .
Libraries hold the objects, such as graphical elements or movie clips, that are used by movies.
Sharing libraries lets multiple movies access objects in a single library. If you reuse objects, be they buttons or movie clips, in multiple movies, each object only downloads once, the first time it's used. After that, other movies share the object that has already been downloaded. The performance boost can be significant, in contrast to having to download every object for each separate movie. Multiple libraries per movie .