With traditional animation method, every principal animation poses are specified by an animator at a specific point in the animation timeline. By setting these poses, an animator can artistically direct how the geometry will be framed in some key events. These poses are in the same sense as how a person may pose for photography session. Note that every shapes and objects in computer graphics are considered as "geometry". With key events specified, the animation software will then automatically fill the intermediary motions between key points, thereby creating continuous motion throughout the timeline without requiring additional works by an animator.