The Big Mac was created by franchisee Jim Delligatti and added to McDonald's nationwide menu in 1968.
Delligatti operated McDonald's restaurants in the Pittsburgh area and developed the sandwich as a larger, more substantial hamburger. Its distinctive construction used two beef patties, a middle bun section, lettuce, cheese, pickles, onions, and Big Mac sauce. McDonald's tested the sandwich before making it available across the United States.
The Big Mac quickly became one of the company's strongest brand symbols. Its name, layered shape, and special sauce gave McDonald's a product that was easy to advertise and recognize internationally. The sandwich's ingredients and nutritional details have varied by market, so local versions should not be assumed to be identical.
The Quarter Pounder is a separate sandwich introduced in 1971. Confusing those two burgers is common because both became major McDonald's menu brands, but only the Big Mac is associated with Delligatti's 1968 national rollout.