These are organic compound required very less in amount for biochemical process. They acts as biological catalyst in various chemical activities of the cell. It having basic nitrogen in them, thus named as vitamins ie. Vital amines or light amines. They are needed to be present in the diet and have no energy value. These are micronutrients which need not to digest. These are grouped in two categories. They are fat soluble and water soluble. The fat soluble vitamins can be dissolved in the fat while water soluble vitamins can be dissolved in water.