Rice is grown in the humid swath of land stretching from Piedmont and Lombardy through the Veneto, where grandmothers often specify exactly which type of shortgrain rice to use in a dish, especially in risotto, in which the grains swell to a creamy plumpness as they cook and absorb the liquid. And what a difference a grain makes! Camaroli, Vialone Nano, Baldo, and Arborio are the preferred types for risotto, although many nonne tout the virtues of the first two with especial fervor. Baldo is a new arrival on the scene. Nonne specifically urge using originario, a very short round rice, for puddings. Never use long-grain American rice for risotto.