Scotch is a type of whisky that must be produced in Scotland, following strict regulations to be legally recognized as such. Here are some key points that define Scotch whisky:

1. Geography: It must be distilled and matured in Scotland.

2. Ingredients: Scotch whisky is made primarily from malted barley, though other grains can be used in grain whisky production.

3. Distillation and Aging: It must be distilled at a Scottish distillery and aged for at least three years in oak casks.

4. Alcohol Content: Scotch must be distilled to an alcohol content of less than 94.8% ABV and bottled at no less than 40% ABV.

5. Types: There are five recognized types of Scotch whisky: Single Malt, Single Grain, Blended Malt, Blended Grain, and Blended Scotch.

Scotch is known for its rich flavors, often characterized by smoky, peaty notes, especially in whiskies from regions like Islay.