Whiskey is distilled liquor brewed with barley, water and yeast as the main raw materials. It is aged in oak barrels for many years, and then mixed and bottled. Its taste is mellow, with unique flavors of smoke, vanilla and fruit, and it is one of the world famous spirits. The producing areas of whisky are mainly concentrated in Scotland, Ireland, the United States and Canada, among which Scotch whisky is the most famous.