Doughnuts can be made using a yeast-based bread dough (raised doughnuts), or a special type of cake batter. Cake doughnuts are often iced with a brightly coloured glace icing or chocolate. Some doughnuts are dredged in cinnamon sugar, while others are filled with jam or custard, briefly soaked in a sugary flavoured solution, or glazed. Some doughnuts are made with apple cider (the non-alcoholic kind) and are common at cider mills and farm markets. Many kinds of doughnuts are eaten warm.
Donuts have become a part of Western culture. The cartoon character Homer Simpson is especially fond of doughnuts, while popular mythology has American police officers addicted to them. There are entire chains of retail stores devoted to the selling of hot fresh doughnuts to eager customers, eg. Dunkin' Donuts, Krispy Kreme, Tim Hortons, Winchell's Donuts, and many other chain stores.
Other sweet fried pastries very similar to doughnuts include churros and fritters.
Doughnuts have a controversial history.One traditional story says that they imported into the USA by Dutch settlers.
A type of doughnut was recorded in the 19th century on the Isle of Wight, UK, with a different recipe from from the type made in mainland Europe.
In France they are called beignets.
In Spain there is something called a churro which is not always thought of as a doughnut, but is made of deep fied sweet pastry and is also popular in the US where it is sometimes referred to as a Spanish Donut (it has a characteristic 'ridged' surface, due to being extruded through a star shaped hole) or Mexican Donut.
In Germany they are called Bismarckss or Berliners and don't have the typical ring shape but instead are solid. (German doughnuts are sometimes called Berlin Doughnuts in the USA.) John F. Kennedy once famously said "Ich bin ein Berliner", which amuses some commentators because it has a double meaning: both "I am a citizen of Berlin" and "I am a jam (jelly) doughnut".
In the Hudson Valley (which includes the Catskill Mountains) in New York State, USA, a doughnut is sometimes called an olicook, which derives from the Dutch Oliekoeke or 'oil cake' (sometimes also called olykoecks). The Dutch themselves also refer to doughnuts as oliebollen (oily balls), although are more like fritters as they contain fruit.
Doughnuts, as ring shaped items, are an important explanatory tool in the science of topology where the ring donut shape (a ring with a circular cross section) is called a torus or toroid, and an example of this can be found in the Poincaré Conjecture.
Washington Irving's reference to "doughnuts" in 1809 in his History of New York is believed to be the first known printed use of the word.