The Full form of NAD is Nicotinamide Adenine Dinucleotide. Money in this world, whether in the form of Dollars or Euros are important forms of currency that a person can exchange for something he want. If you want an ice-cream you have to pay a certain amount of dollars and cents for the ice-cream. In the cell, the currency is not dollars and cents, but molecules. In particular, for energy and respiration, the currency is electrons and hydrogen. In order to produce energy, the cell has to use electrons and hydrogen. But how does the cell get the electrons and hydrogen it needs to make and store energy? That is where the electron carriers come in, the carriers of cellular money. One of these carriers is called Nicotinamide Adenine Dinculeotide or NAD+ for short. NAD+ is an important conveyor of hydrogen and electrons for the cell and is essential for the continued production of energy (ATP) by the mitochondria. The vitamin B3 is used by the cell to form part of the molecule NAD+. The important part of NAD+, the part that holds on to cellular currency, comes from the part of the molecule formed from vitamin B3. NAD+ is able to accept and carry hydrogen and two electrons.