Oak barrels are containers made from the wood of oak trees, commonly used for aging beverages like wine and whiskey. The wood's natural properties allow it to impart unique flavors and aromas to the liquid inside, enhancing the overall taste. The barrels are typically constructed using staves, which are curved pieces of wood that fit together tightly. The aging process in oak barrels also allows for the gradual interaction between the liquid and the air, which can soften harsh flavors and develop complexity. Different types of oak, such as American oak and French oak, contribute distinct characteristics, making the choice of barrel an important factor in the production of fine spirits and wines.