Beans have been part of our diet in every corner of the earth from time immemorial. Esau traded his birthright for a bowl of lentils in Genesis, red and black beans were a part of Motezuma's diet, and peanuts (which are really a bean, and not a nut) and lima beans have been depicted in ancient pre-inca gold and pottery as food fit for gods.
Botanically speaking most of them belong to the leguminosae family and share a common characteristic: they all come in a pod.
Dried beans, are just that: beans which have been sun dried until the pod becomes crackly and pops open and the beans can be collected from the bottom of the pile.
Nutritionally essential for the world's diet, beans supply vast amounts of protein without the fat, and they offer many vitamins, mineral salts and plenty of fiber.
At one point in history beans were displaced from the finer tables because of their "gassy" reputation. This is easily prevented: never cook beans in the water in which they were soaked. After soaking, drain, and place beans in fresh boiling water. Lentils do not require any soaking.