A cooper is a skilled craftsman who makes wooden casks, barrels, vats, buckets, tubs, troughs, and other similar containers from timber staves that are usually heated or steamed to make them pliable). The word "cooper" is derived from Middle Dutch or Middle Low German kūper cooper from kūpe cask, in turn from Latin cupa tun, barrel). The work of a cooper is essential to commerce and daily life, and coopers have been around for centuries. They are responsible for making, tending to, and repairing wooden barrels that were used to ship and trade a wide variety of goods, including potable water, eggs, fish, wine, glass, cotton, tobacco, cement, and whaling oil. Coopers divided their work into three basic categories: "Dry" cooperage - barrels to hold dry goods like nails, tobacco, fruits, and vegetables. "Drytight" cooperage - barrels that kept moisture out of goods like flour or gunpowder; and "Wet" or "Tight" cooperage - barrels for long term storage and transportation of liquids. Coopers require skill, intelligence, and strength, and the tools of the trade are often handed down for generations. The craft of coopering has remained unchanged over the last millennium, and coopers still use traditional methods to handcraft beautiful barrels, fermentation vessels, tubs, and kiokes.