Traditionally, vodka is made by the distillation of fermented wheat, rye, or, potatoes, though some modern brands use other substances, such as fruits or sugar. Vodka will have been distilled to a high strength then filtered through charcoal to remove impurities before bottling. While most vodkas are unflavored, many flavored vodkas have been produced in traditional vodka-drinking areas and are increasing in popularity amongst cocktail drinkers.