The Big Mac was marketed as the “sandwich with the middle bun” when it launched nationally in 1968.
Franchisee Jim Delligatti developed the sandwich in the 1960s at his McDonald’s restaurants in the Pittsburgh area. It used two beef patties, a three-part sesame-seed bun, lettuce, cheese, pickles, onions, and the sauce that became closely associated with the product. After regional testing, McDonald’s introduced the Big Mac across the United States in 1968.
The middle bun was a major visual and structural distinction. It helped separate the two patties and gave the sandwich its unusually tall profile. McDonald’s advertising emphasized that feature because it made the product immediately different from a standard hamburger.
The Big Mac became more than a menu item: it became an international brand symbol. The Big Mac Index later used the sandwich’s price as an informal way to compare currencies. That economic index is separate from McDonald’s advertising, although both rely on the sandwich’s global familiarity.