Maize (Zea mays L.), a member of the grass family Poaceae (synonym Gramineae), is the most important human dietary cereal grain in Latin America and Africa and the second most abundant cultivated cereal worldwide. Originating in varying altitudes and climates in the Americas, where it still exhibits its greatest diversity of types, maize was introduced across temperate Europe and in Asia and Africa during the sixteenth and seventeenth centuries. It became a staple food of Central Europe, a cheap means of provisioning the African-American slave trade by the end of the eighteenth century, and the usual ration of workers in British mines in Africa by the end of the nineteenth century. In the twentieth century, major increases in maize production, attributed to developments in maize breeding, associated water management, fertilizer response, pest control, and ever-expanding nutritional and industrial uses, have contributed to its advance as an intercrop (and sometimes as a staple) in parts of Asia and to the doubling and tripling of maize harvests throughout North America and Europe. High-yield varieties and government agricultural support and marketing programs, as well as maize’s biological advantages of high energy yields, high extraction rate, and greater adaptability relative to wheat or rice, have all led to maize displacing sorghum and other grains over much of Africa.

On all continents, maize has been fitted into a wide variety of environments and culinary preparations; even more significant, however, it has become a component of mixed maize-livestock economies and diets. Of the three major cereal grains (wheat, rice, and maize), maize is the only one not grown primarily for direct human consumption. Approximately one-fifth of all maize grown worldwide is eaten directly by people; two-thirds is eaten by their animals; and approximately one-tenth is used as a raw material in manufactured goods, including many nonfood products.