Hmmmm, probably we have not been doing a good job of answering your first question.

Forgive me if I try to answer these questions in a little more depth, particularly so as to give some answer to the last question as well.

 

OK, in Vue, a "poseable object" consists of a conventional 3d mesh and a "skeleton" of joints to which that mesh is bound. (Click on each of the illustrations to expand them to a good viewing size.)

Here is the mesh for one of my adult sperm whale models, with the skeleton for it displayed in green.