Oleic acid is a molecule found in the oil from the small green fruit of the olive tree. Like many other oils and fats, olive oil is a triglyceride. It is also unsaturated and contains 18 carbons in total. The triglyceride can be put through a process known as saponification to produce glycerol and three molecules of soap. Olive oil has been a valued trade item all over the world for thousands of years. Many civilizations, such as Athens, have been built around olive trees and the folk lore about them. The oil was used in many different ways around the Mediterranean. It was used for lamps, cosmetics, massage oils, medicines, and smelling oils. In my opinion, oleic acid has changed the world and continues to change the world today. Whether it’s the multitude of cities built from the olive trees, or the culture built off of the folk lore, or the amazing food that comes from olive oil, or even just the lusciousness it brings to your hair, olive oil is used by millions of people every day. I personally agree with the author in the inclusion of this chapter about Oleic acid because it has and will continue to change our everyday lives.