Vitamins are essential to human health. Here, learn about each of the 13 vitamins , including good sources and how they help. Learn more here. Vitamin , any of several organic substances that are necessary in small quantities for normal health and growth in higher forms of animal life. Vitamins generally cannot be synthesized in amounts sufficient to meet bodily needs and therefore must be obtained from the diet or from some synthetic source. Different animals, plants and other living species have both, common names and scientific names. Similarly, all the vitamins have their respective scientific names. This nomenclature is mainly based on their compositions, physical and chemical properties and their biochemical functions. What are Vitamins? Vitamins are the organic compounds which help in performing biological functions of a living organism. It is a vital nutrient that should be included in our daily diet in the required ... Find out from WebMD's slideshow which vitamins and minerals your body needs, what they do, and what foods you can eat to get them..