What you see here is the Caster Assembly made in both AutoCAD and Inventor. These are software programs for machanical design. This was assigned to be completed in both software programs. I personally prefer doing this assignment in Inventor because I have become more accustomed to using Inventor as opposed to AutoCAD. Inventor is much easier to make 3-D parts than it is an AutoCAD, though AutoCAD still have it's place.