mdd is a file system for carrying Point Level Animation, a system for baking complex scenes and animations into a simple format with an obj file and points that just works. For example, you can also use mdd to send a Poser figure directly to Marvelous Designer from Daz4, with conforming cloth and animation and all.

Genesis, V4, V4 WM, Anastasia, Antonia, all is treated the same way.