What was the name of McDonald's original fast-service operating system?

McDonald's original fast-service operating system was called the Speedee Service System.

Richard and Maurice McDonald developed the system at their San Bernardino, California, restaurant after redesigning their business around speed and consistency. They reduced the menu, standardized preparation, and organized kitchen work in an assembly-line fashion.

The system helped distinguish McDonald's from traditional drive-in restaurants, where customers often waited for customized meals. Its name also inspired Speedee, the early mascot who represented quick service. The approach later became a foundation for the modern fast-food franchise model.

The Speedee Service System should not be confused with a slogan or a restaurant name. It described a method of operation. Ray Kroc later expanded McDonald's through franchising, but the system itself originated with the McDonald brothers before Kroc joined the company.