What is the difference between a design patent and a utility patent?

90% of all patents issued by the U.S. Patent office are utility patents.  A utility patent is for the invention of a new process, machine, product or composition of matter; or a useful improvement of one of those things.  A utility patent typically protects the owner against others making, selling or using their invention for a period of 20 years in the U.S.

A design patent is issued for a new or original design embodied in or applied to a product.  In other words, a design patent is specific to ornamental aspects of a product.  This type of patent protects the owner for a period of 14 years, but only for ornamental features, not for functional features.