Vitamin

Vitamins. Your body needs them. You can't make the essential ones, but you can make the non-essential ones. They come in water-soluble and fat-soluble. They get stored in different places in your body, and your body keeps them for different lengths of time.

Essential vitamins

 * Vitamin b12 (wikipedia)

Questions

 * What is a vitamin, besides a thing your body needs in order to work right?