What was the name of McDonald's service system that emphasized preparing food quickly in the 1940s?

McDonald's early fast-food operating model was called the Speedee Service System.

Richard and Maurice McDonald developed the system after changing their San Bernardino, California, restaurant into a highly organized hamburger operation. The brothers simplified the menu, standardized portions, reduced table service, and arranged the kitchen so workers could prepare food quickly and consistently.

The system became central to McDonald's identity before the company grew into a global chain. Its emphasis on speed and uniformity influenced the wider fast-food industry, where customers came to expect inexpensive food prepared in a short time. The branding also produced the Speedee mascot, which visually linked the restaurant to quick service.

The Speedee Service System is sometimes mistaken for a slogan or a menu item. It was an operating system for restaurant production and service. Ray Kroc later expanded McDonald's through franchising, but the basic efficiency principles originated with the McDonald brothers.