Agaricus bisporus—known variously as the common mushroom, button mushroom, white mushroom, table mushroom, champignon mushroom, crimini mushroom, Swiss brown mushroom, Roman brown mushroom, Italian brown, Italian mushroom, cultivated mushroom, or when mature, the Portobello mushroom—is an edible basidiomycete mushroom native to grasslands in Europe and North America. Agaricus bisporus is cultivated in more than 70 countries and is one of the most commonly and widely consumed mushrooms in the world.