There are many types of vitamins; vitamin A, B, C, D, E and K. A vitamin is an organic compound, a nutrient necessary for living organisms to stay alive.   

The word vitamin is derived from vita which means life and amin, derived from amino acids. Vitamins are organic molecules.

Different types of food provides different types of vitamins. It is also possible to obtain vitamins through vitamin pills although the precise effects of these are still up to debate.

Keynote speakers dealing with vitamins may choose to focus on the different types of vitamins, their effect, etc.