Cereals or grains are mostly grasses cultivated for their edible brans or fruit seeds. Cereal grains are members of the monocot family Poaceae. There are 8,000 different types of grass.Cereal grains are grown in greater quantities and provide more energy worldwide than any other type of crop; they are therefore called as staple crops. They are also a rich source of carbohydrates.

In some developing nations, grain in the form of rice, wheat, or maize constitutes a majority of daily sustenance.

In developed nations, cereal consumption is more moderate and varied but still substantial.

The word cereal is derived from the word Ceres, the name of the pre-Roman goddess of harvest and agriculture. Cereal plants grow in all parts of the world, except very dry deserts and the ice-covered poles. Different climates grow different cereals - wheat and maize grow in mild climates, oats and barley love cooler, damper climates, rice needs waterlogged, boggy soils, and sorghum, millets and teff can grow in hot, dry tropical places.

Cereal plants have to be planted every year and at the end of the summer, when they have produced ripe seeds, they die down.
Like all seeds, cereals are very nutritious because they contain all the nutrients the embryo plant needs to start growing.