The common bean has been cultivated for over 8,000 years. It is one of the first
vegetables used in human agriculture. Beans were introduced to Europe in the
16th century.
There are over 4,000 cultivars of beans today.
The term "string bean" originated because the original bean cultivars had a
fibrous string that ran along the seam of the bean. The string was noticeable when
you snapped off the ends. Improved cultivars developed in the early 20th century
no longer had this string (which was obviously not very palatable).
The U.S. produces around 800,000 tons of beans each year. Wisconsin produces
the most (~300,000 tons) with California in second place.
Beans contain oligosaccharides. These are complex sugars that cannot be broken
down by humans. However, bacteria in the intestines do have the necessary
enzymes. This bacterial digestion of the oligosaccharides causes gas build-up and
ultimately flatulence.
Beans are a legume, and have the ability to fix nitrogen directly from the air.
Nitrogen fertilizers are generally required only in small amounts or not at all.
American indians would often plant beans alternating with corn (a heavy nitrogen
feeder). The beans would vine up the corn plants as they grew (all varieties at the
time were "pole beans", as "bush bean" cultivars had not been developed). The
excess nitrogen from the beans would feed the corn, and the corn made a handy
trellis for the beans.
The Navy Bean got its name for being a staple in the galley of Naval ships in the
19th century. No one seems to know what it was called before then.