McDonald's named its signature double-decker hamburger the Big Mac when it debuted in 1967.
The sandwich was created by franchisee Jim Delligatti, who operated McDonald's restaurants in the Pittsburgh area. It used two beef patties, a middle bun section, lettuce, cheese, pickles, onions, and sauce, giving the chain a larger, more distinctive product for customers seeking a substantial burger.
The Big Mac initially appeared in select markets before becoming a national menu item in the United States. Its name helped turn the sandwich into more than a menu product: it became one of McDonald's most recognizable branded food names.
The Big Mac is sometimes confused with the Quarter Pounder because both are flagship McDonald's burgers. The key distinction is that the Big Mac is identified by its two-patty, three-part bun construction, while the Quarter Pounder is named for the pre-cooking weight of its beef patty.