Designation for a cylindrical container, usually bulbous, made of various materials such as wood, metal, plastic or ceramic for storing liquids. In viticulture, barrels are mostly made of wood because this material is breathable and allows a measured influx of oxygen, which is usually desirable during wine ageing. For filling and emptying, it has a small opening called a bung (bunghole). It can also be open on one side and is then fitted with a lid. In the case of large barrels, a means of entry in the bottom (barrel latch) enables cleaning for one person. The roller shape enables effortless handling, moving and space-saving stacking. Barrels of different types and volumes play an important role in terms of finishing. In the past, the barrels were manufactured by the craftsman profession of the cooper. Today, however, wooden barrels are mostly manufactured industrially in companies known as tonnelleries. The historical development is described in detail under Wine Vessels.