It typically requires a patent attorney to define all the nuances between trade secrets, patents, and trademarks, however a few basics don't require a patent attorney for a generic understanding.

Patent infringement is considered an infringement on a product, or a p
roduct enhancement that is patented to an existing inventor or company. For a period nearing twenty years, an inventor or company can hold exclusive rights to a patent, and anyone who markets or presents a product that can only reasonably used for the same purpose is guilty of patent infringement.