McDonald's introduced the Big Mac in 1968, and it became a major part of the company's brand identity.
The sandwich was created by franchisee Jim Delligatti, who operated McDonald's restaurants in the Pittsburgh area. Its distinctive construction used two beef patties, a middle bun section, lettuce, cheese, pickles, onions, and Big Mac sauce.
The Big Mac gave McDonald's a signature product that could be recognized separately from its broader hamburger menu. Its name, layered appearance, and later advertising helped make it one of the company's most internationally identifiable items.
The Big Mac is sometimes confused with the Quarter Pounder because both became major McDonald's burgers. The Quarter Pounder was introduced later, in 1971. The Filet-O-Fish also predates the Big Mac, having been introduced in 1963.