Scotch whiskies are generally distilled twice, although some are distilled a third time and others even up to twenty times. Scotch Whisky Regulations require anything bearing the label "Scotch" to be distilled in Scotland and matured for a minimum of three years in oak casks, among other, more specific criteria. An age statement on the bottle, in the form of a number, must reflect the age of the youngest Scotch whisky used to produce that product. A whisky with an age statement is known as guaranteed age whisky. Scotch whisky without an age statement may, by law, be as young as three years old.
The basic types of Scotch are malt and grain, which are combined to create blends.
Many, though not all, Scotch whiskies use peat smoke to treat their malt, giving Scotch its distinctive smokey flavor. Scotch malt whiskies are divided into five main regions: Highland, Lowland, Islay, Speyside and Campbeltown.