Turmeric is another common Indian spice. Grown as a rhizome, it can be used fresh (like ginger) or dried. It has been known to have a host of health benefits and is used in a lot of spice mixes and curries. The flavor of fresh turmeric is slightly stronger than dried, and it stains very easily, so make sure you are careful with your clothes and utensils while using it.
It has a pungent, earthy fragrance; I use it in small quantities to give my curries a beautiful golden color.