Phaseolus vulgaris, the common bean (also known as the string bean, field bean, flageolet bean, French bean, garden bean, green bean, haricot bean, pop bean, or snap bean), is a herbaceous annual plant grown worldwide for its edible dry seed (known as just "beans") or unripe fruit (green beans). Its leaf is also occasionally used as a vegetable and the straw as fodder. Its botanical classification, along with other Phaseolus species, is as a member of the legume family Fabaceae, most of whose members acquire the nitrogen they require through an association with rhizobia, a species of nitrogen-fixing bacteria.