Single Malt: The whisky is produced by a single distillery and is made exclusively from barley.
Blended: The most popular category of whisky, created by blending whiskies from more than one distillery, using barley or other grains as the base ingredient.
Grain: It is mainly produced from other grains (e.g. wheat, corn). It is lighter in taste than Malt and is often used in Blends.