The Timeline is where you synchronize the animation of your objects.
When you select an object on the Stage, the corresponding object timeline is highlighted:
Per animation effect that you add, an additional sub-timeline is added for that specific effect. Your can hide these sub-timelines using the small arrow left of the object name:
The lines on the Timeline also represent Object Layers: when two objects visually overlap each other on the stage, the object higher on the Timeline will be in front of the object lower on the Timeline. You can drag objects to higher or lower layers by clicking and dragging their name:
You can also change the order of an object on the Stage using the rightclick-menu.
Once you’ve synchronized your objects, you can preview your animation by clicking the Play button. Click the fast-forward or rewind buttons to move forward or backward on the Timeline.
You can also collapse and expand the Timeline view: When you collapse the Timeline view, you will just see the Clips you have created. When you expand the Timeline view, you see all the objects and animations contained in your Clips. These buttons are found on the left side of the Editor, directly above the Timeline. The view you selected changes color from gray to blue:
You can also scroll-zoom in on the Timeline: This is a new way of navigting the Timeline. This screenshot shows the old way and the new way of doing this: