Combination of merchandise departments. Each merchandise group is managed by a. general merchandise manager (GMM) Merchandise Group. Departments are managed by a divisional merchandise manager (DMM), Department. A group of items targeting the same customer type (example, girls sizes 4-6) . A buyer is responsible for a merchandise classification. Classification. A category is made up of an assortment of. items the consumer sees as substitutes for. one another (example, size 4-6 dresses) Category. The smallest unit available for inventory control. Size, color, style, brand. SKU.