A breakfast cereal (or just cereal) is a food made from processed grains that is often eaten with the first meal of the day. It is often eaten cold, usually mixed with milk (e.g. cow's milk, soy milk, rice milk, almond milk), juice, water, or yogurt, and sometimes fruit, but may be eaten dry. Some companies promote their products for the health benefits from eating oat-based and high-fibre cereals. Cereals may be fortified with vitamins. Some cereals are made with high sugar content. Many breakfast cereals are produced via extrusion. The breakfast cereal industry has gross profit margins of 40-45%, 90% penetration in some markets and steady and continued growth throughout its history.
http://en.wikipedia.org/wiki/Breakfast_cereal
Since 1998, breakfast