There are 3 basic sizes of rice, long-grain, medium and short-grain. The size of the rice determines the cooking texture and flavor. Each rice can be used for specific dishes and recipes.
Long-grain rice is fluffy when cooked, so it tends to separate. The grains have a firm, dry texture, and are best for side dishes, pilafs, stir-fry and salads. Long-grain rice is also slim and lengthy, nearly four to five times longer than it is wide. This type of rice includes American long-grain white and brown rice, Basmati rice, and Jasmine rice.
Medium-grain rice is tender, moist, and stickier than long-grain rice when cooked. Shorter and wider than its long-grain counterpart, medium-grain rice is about two to three times longer than it is wide. Arborio and Valencia are medium-grain varieties used in Italian risotto. The Spanish varieties of Arroz Negroni and Bomba rice are used in paella.
Short-grain rice is the most sticky and soft when cooked. This fat, and round grain has an extra starch which gives it its sticky and clumpy texture. American short-grain brown rice and sushi rice are common varieties of short-grain rice. Short-grain rice is perfect for sushi and pudding.