1, dm is the abbreviation of English Directmail, which means express commodity advertisement, and DM market means express commodity advertisement market. 2.EM is the abbreviation of EmergingMarket, which generally refers to mature or developed markets. Newsletter advertisements are usually printed in color on the front and back of 8-yard or 16-yard advertising paper, and widely publicized by mail, fixed-point delivery and selective delivery to consumers' residences, which is one of the most important promotional means in supermarkets.