Fatty acids are carboxylic acids, having a long aliphatic chain of saturated or unsaturated hydrocarbons. These acids are broadly classified into various forms on the basis of their length, saturation or unsaturation, even or odd content of carbon, and by linear or branched structures. On the basis of length, they are categorized into short-chain, medium-chain, long-chain and very long chain fatty acids. Some of the reactions exhibited by fatty acids are saponification, hydrogenation, rancidity and ozonolysis. Fatty acids have a wide variety of applications. They are used in the production of soaps, and as emulsifiers, anti-foam agents, texturizing agents, etc. This book unravels the recent studies on fatty acids. It will also provide interesting topics for research which interested readers can take up. Students, researchers, experts and all associated in this area of study will benefit alike from this book.