4.1 What Is a Skeleton?
Now that you are comfortable with Hierarchies, Euler Rotations, and Joint Orients, it’s time to delve into the whole purpose for having all this stuff in a 3D engine: skeletons. A skeleton is a multitiered, hierarchy of joints that represent in some way the manner in which your intended model or object is going to move. It doesn’t always have to be in regard to an actual character; in fact, skeletons and hierarchical movements can be applied to all sorts of mechanics and other properties of 3D movement. The important thing that you need to know is how multiple rotations and translations are managed in a hierarchy, and what exactly you’ll be doing with it.
4.2 What Are Skeletons Used For?