What are peanuts?
The peanut plant (Arachis hypogaea) does not produce nuts in its proper sense, but a seed, which is found underground in pods. The plant belongs to the pea family, and is nitrogen-fixing in the same way as the pea plants grown in Sweden. That the pod, and the seed, develop underground, the peanut plant is basically alone among commercialized crops. The plant is believed to have originated in northern Argentina or Brazil, but the original species no longer exists in the wild. However, several different types of improved varieties are grown in many tropical countries in the world.