Similar to many digital animation programs, Edge employs the concept of "tweening" between keyframes. In traditional cell-based animation, a master animator would draw out certain key frames for an animation sequence and the frames in between these key frames would be created by apprentice or lower-ranked members of the animation team. The goal was always to create a smooth transition between each key frame created by the master animator, which would result in a completed animation sequence.
This process is performed programmatically within Edge. As keyframes are placed along the Timeline, Edge will fill in the time between with motion determined from the values gathered by adjacent keyframes. As authors, we have the additional ability to provide the tweening engine with instruction sets based upon a variety of easing equations. This allows a more natural flow between keyframes, and can also be used to achieve certain effects such as an elastic or bounce motion.