The Big Mac was introduced by McDonald's in 1968 and became one of the chain's best-known global brand symbols.
The sandwich was created by franchisee Jim Delligatti, who operated McDonald's restaurants in the Pittsburgh area. Its distinctive construction uses two beef patties, a middle bun section, lettuce, cheese, pickles, onions, and Big Mac sauce.
The product gave McDonald's a highly recognizable signature item that could be marketed separately from the general menu. Its name, layered structure, and advertising jingle helped make it one of the most identifiable fast-food products in the world.
The Big Mac is sometimes confused with the Quarter Pounder because both are flagship McDonald's burgers. They differ in construction: the Big Mac is defined by its three-part bun and two smaller patties, while the Quarter Pounder centers on a larger single patty.