Patent, either patent leather or patent pu, the latter being a man made material, has a very shiny, almost mirror like appearance. Pu, short for polyurethane, is a semi-shiny to non-shiny man made material designed to be less expensive than leather. Stretch, either patent or pu, is a thin, stretchable material, which allows it to fit to the contours of the feet or legs. PVC is man made material that looks like leather, but, is less expensive. Leather, usually has a supple and comfortable feel and with a texture pattern, is the highest quality material of all used in shoemaking, it is very comfortable and stretches to your size after wearing it awhile.