Wendy's is an American international fast food restaurant chain founded by Dave Thomas on November 15, 1969, in Columbus, Ohio. Its headquarters moved to Dublin, Ohio, on January 29, 2006. As of December 31, 2018, Wendy's was the world's third-largest hamburger fast-food chain with 6,711 locations, following Burger King and McDonald's. On September 29, 2008, the company merged with Triarc Companies Inc., the publicly traded parent company of Arby's; Wendy's headquarters remained in Dublin. Triarc then became known as Wendy's/Arby's Group, and later as the Wendy's Company following the sale of Arby's to Roark Capital Group.

A fast-food restaurant, also known as a quick-service restaurant (QSR) within the industry, is a specific type of restaurant that serves fast-food cuisine and has minimal table service. The food served in fast-food restaurants is typically part of a "meat-sweet diet", offered from a limited menu, cooked in bulk in advance and kept hot, finished and packaged to order, and usually available for take away, though seating may be provided. Fast-food restaurants are typically part of a restaurant chain or franchise operation that provides standardized ingredients and/or partially prepared foods and supplies to each restaurant through controlled supply channels. The term "fast food" was recognized in a dictionary by Merriam–Webster in 1951.