By Harold McGee
Millet is the name used for a number of different grains, all of them with very small round seeds, 1–2 mm in diameter (species of Panicum, Setaria, Pennisetum, Eleusine). The millets are native to Africa and Asia, and have been cultivated for 6,000 years. They’re especially important in arid lands because they have one of the lowest water requirements of any cereal, and will grow in poor soils. The grains are remarkable for their high protein content, from 16 to 22%, and are popped and also made into porridge, breads, malts, and beers.