A croissant is a buttery, flaky, viennoiserie or Vienna-style pastry named for its well-known crescent shape. Croissants and other viennoiserie are made of a layered yeast-leavened dough. The dough is layered with butter, rolled and folded several times in succession, then rolled into a sheet, in a technique called laminating. The process results in a layered, flaky texture, similar to a puff pastry.
Crescent-shaped food breads have been made since the Middle Ages, and crescent-shaped cakes possibly since antiquity.
Croissants have long been a staple of Austrian and French bakeries and pâtisseries. In the late 1970s, the development of factory-made, frozen, pre-formed but unbaked dough made them into a fast food which can be freshly baked by unskilled labor. The croissanterie was explicitly a French response to American-style fast food, and today 30–40% of the croissants sold in French bakeries and patisseries are frozen. Today, the croissant remains popular in a continental breakfast.