This document discusses cereals, starches, and their nutritional significance. It explains that cereals are important food crops that are a major source of calories worldwide. Starch is the main component of cereals and tubers, and is found in seeds, roots, and tubers. Common sources of starch include corn, potatoes, and cassava. Starches have various roles and properties in food including thickening, binding, and retaining moisture. Cereals and starches provide nutrients like carbohydrates, protein, vitamins, and minerals.