A doughnut, or donut, is a sweet, deep-fried piece of dough or batter. The two most common types are the torus-shaped ring doughnut and the filled doughnut, a flattened sphere injected with jam/jelly, cream, custard, or another sweet filling. A small spherical piece of dough, originally made from the middle of a ring doughnut, may be cooked as a doughnut hole.