All Bourbon is Whiskey, but not all Whiskey is Bourbon. The main difference is the type of barrels in which the alcohol is aged during production. Bourbon must be aged in “new charred oak barrels”, whereas Whiskey can be aged in used oak barrels. 95% of the world's supply of Bourbon comes from Kentucky. Buy the best, award winning premium Bourbons & American Whiskies right here in our online liquor store, nationwide delivery.