Barley is a cereal grain, one of the earliest domesticated crops, originating in the Fertile Crescent of the Middle East and now grown widely in temperate regions, including Russia, Canada, Germany, France, and the United States.
In cooking, barley is most often used as pearl barley (hulled and polished, so it cooks faster and has a softer texture) or hulled barley (with only the inedible outer husk removed, retaining more bran and taking longer to cook). It has a chewy texture and nutty, slightly sweet flavor, and is used in soups, stews, risotto-style dishes, pilafs, salads, and some breads.
Barley pairs well with mushrooms, root vegetables, and herbs like thyme and rosemary, and complements acidic ingredients such as tomatoes and vinegar.
Barley contains gluten and is not suitable for a gluten-free diet; it should not be confused with gluten-free grains such as rice, quinoa, or buckwheat.