Also known as maize, grain corn was the chief source of nourishment for thousands of years, sustaining the Mayas, Aztecs, Incas and the Indian peoples of North and South America. After the early settlers arrived in America, corn was introduced to Europe and is now cultivated in Africa, China, Russia and other parts of the globe. Originally corn was grain corn; now it's used for cattle feed and a variety of industrial applications. Sweet corn, as such, is a relatively recent development, becoming popular chiefly since the American Civil War period.