[1] A wide variety of plant species provide edible seeds; most are angiosperms, while a few are gymnosperms.
As a global food source, the most important edible seeds by weight are cereals, followed by legumes, nuts,[2] then spices.
Cereals (grain crops) and legumes (pulses) correspond with the botanical families Poaceae and Fabaceae, respectively, while nuts, pseudocereals, and other seeds form polyphylic groups based on their culinary roles.
Grains can be consumed in a variety of ways, all of which require husking and cooking, including whole, rolled, puffed, or ground into flour.
Many cereals are present or past staple foods, providing a large fraction of the calories in the places in which they are eaten.