Each scene in a Flash document can consist of any number of layers. Layers and layer folders organize the components of an animation sequence and separate animated objects so they don’t erase, connect, or segment each other. To tween the movement of more than one group or symbol at once, each must be on a separate layer. Typically, the background layer contains static artwork, and each additional layer contains one separate animated object.

When a document has several layers, tracking and editing the objects on one or two of them can be difficult. This task is easier if you work with the contents of one layer at a time. Layer folders help you organize layers into manageable groups.