A patent is an interesting concept that has evolved from the Middle Ages. Back then, it was a document granting privilege by the King and it has evolved into a right that is granted to inventors by the laws of a country. It's actually a kind of protection for inventors to ensure they have the chance to make a profit from their inventions which will reward them for the time, money and energy they spent developing it. This is what makes the world of capitalism go around. If capitalism is to continue successfully then we must be provided goods and services to buy and use. Realistically we will not buy the same things over and over, year after year. What we will buy is new and improved models which are variations of the same thing. They may be bigger, smaller, different colors, round instead of square, square instead of round, or have shiny finishes, don't finishes, smooth or rough surfaces, etc. The types of changes are endless so we need to keep modern. Think about it, every year things change, cars, clothing, housing, appliances, furniture, luggage, fabrics, to mention just a few. They do the same thing for us really, a toaster is a toaster no matter the color or shape. It is the same for a car. In a lot of cases, everything old is new again. In order to fuel this cycle,  incentives must be provided to those who assist perpetuating it inventors. How do they make money? Patents are in fact society's contract with inventors. Once granted, they can be bought, sold, licensed, exchanged and given away. Patents are known as intellectual property and recognized as being intangible which means although they cannot be touched, they are an asset. There are other categories of intellectual property, trademarks, copyrights and trade secrets, but we are not concerned with them for now.