Vitamins may be defined as potent organic substances which are essential for the normal growth & maintenance of life of humans & animals who are not able to synthesize in adequate quantity (Except vit-D) & are obtained from the diet. Water Soluble Vitamin B1 (Thiamine) Vitamin B2 (Riboflavin) (Vit- G) Vitamin B3 (Niacin) Vitamin B5 (Pantothenic acid)S Vitamin B6 (pyridoxine) Vitamin B9 (Folic acid) Vitamin B12 (Cyanocobalamin) Vitamin C (Ascorbic acid)  Fat Soluble Vitamin A (Retinol) Vitamin D2 (Calciferol) Vitamin D3 (Ergocalciferol) Vitamin E (Tocopherol) Vitamin K (Phyto menadione)  Fat & Water Soluble Vitamin B7/ Biotin / Vitamin H