Doughnut chains are popular retail businesses that specialize in selling a variety of doughnuts. These chains often offer a wide selection of flavors and styles, including glazed, filled, and specialty doughnuts. Many doughnut chains also serve coffee and other beverages, creating a cozy atmosphere for customers to enjoy their treats. Some well-known doughnut chains include Krispy Kreme and Dunkin'. These establishments often have multiple locations, making them easily accessible to customers. Doughnut chains frequently engage in marketing promotions and seasonal offerings to attract new customers and retain loyal ones.