McDonald's original restaurant service system was called the Speedee Service System.
Richard and Maurice McDonald developed the system at their San Bernardino, California, restaurant after redesigning operations around speed, consistency, and a limited menu. They applied assembly-line principles to food preparation, reducing the number of items and assigning workers specialized tasks.
The system helped establish the operational model later associated with fast food: standardized preparation, rapid service, inexpensive products, and a restaurant layout designed for repeatable production. Its name also inspired Speedee, the early McDonald's mascot.
The Speedee Service System predates Ray Kroc's expansion of McDonald's as a major franchise business. Kroc did not invent the brothers' original system; he recognized its potential, became their franchise agent, and later built the larger McDonald's corporation around the model.