A multivitamin is a dietary supplement that contains essential vitamins and minerals needed for good health. It is designed to provide nutritional support when an individual's diet may be lacking in certain key nutrients, or if they have specific nutritional needs due to age, gender, or other factors. Multivitamin supplements typically contain a combination of vitamins A, C, D, E, K, B-complex vitamins (such as B1, B2, B3, B5, B6, B7, B9, and B12), folic acid, biotin, pantothenic acid, calcium, iron, magnesium, zinc, copper, manganese, chromium, molybdenum, and selenium. These nutrients work together to support overall health and well-being, including the growth and repair of tissues, the production of energy, and the maintenance of a strong immune system.