How many classes of vitimans are there?

There are 13 essential vitamins, which are categorized into two main classes: water-soluble vitamins and fat-soluble vitamins. Water-soluble vitamins include the B-complex vitamins and vitamin C, while fat-soluble vitamins consist of vitamins A, D, E, and K. Each class plays unique roles in the body, contributing to various physiological functions and overall health.