Barrel

A barrel, cask, or tun is a hollow cylindrical container, traditionally made of wooden staves bound by wooden or metal hoops. Traditionally, the barrel was a standard size of measure referring to a set capacity or weight of a given commodity. For example, in the UK a barrel of beer refers to a quantity of 36 imperial gallons. Wine was shipped in barrels of 119 litres (31 US gal). A small barrel is called a keg.

Modern wooden barrels for wine-making are either made of French common (Quercus robur) and white oak (Quercus petraea) or from American white oak (Quercus alba) and have typically these standard sizes: "Bordeaux type" 225 litres (59 US gal) and "Cognac type" 300 litres (79 US gal). Modern barrels and casks can also be made of aluminum, stainless steel, and different types of plastic, such as HDPE.

Someone who makes barrels is called a "barrel maker" or cooper. Barrels are only one type of cooperage. Other types include, but are not limited to: buckets, tubs, butter churns, hogsheads, firkins, kegs, kilderkins, tierces, rundlets, puncheons, pipes, tuns, butts, pins, and breakers.

Barrels have a variety of uses, including storage of liquids such as water and oil, fermenting wine, arrack and sake, and maturing beverages such as wine, cognac, armagnac, sherry, port, whiskey and beer.