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Cereals, grains or cereal grains, are grasses (members of the monocot families Poaceae or Gramineae)The seeds of several other plants, such as buckwheat, are also used in the same manner as grains, but since they are not grasses they cannot strictly be called such cultivated for the edible components of their fruit seeds (botanically, a type of fruit called a caryopsis) - the endocarp, germ and bran. Cereal grains are grown in greater quantities and provide more food energy worldwide than any other type of crop; they are therefore staple crops. In their natural form (as in whole grain), they are a rich source of vitamins, minerals, carbohydrates, fats and oils, and protein. However, when refined by the removal of the bran and germ, the remaining endocarp is mostly carbohydrate and lacks the majority of the other nutrients. In some developing nations, grain in the form of rice, wheat, or maize (in American terminology, corn) constitutes a majority of daily sustenance. In developed nations, cereal consumption is more moderate and varied but still substantial. The word ''cereal'' derives from ''Ceres'', the name of the Roman goddess of harvest and agriculture.

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