The Big Mac became McDonald's first nationally marketed sandwich featuring two beef patties in 1968.
The sandwich was created by Jim Delligatti, a McDonald's franchisee who operated restaurants in the Pittsburgh area. Its stacked construction, middle bun layer, special sauce, lettuce, cheese, pickles, and onions gave the product a distinctive appearance that worked especially well in national advertising.
The Big Mac became more than a menu item: its name, packaging, and memorable structure became part of McDonald's global product branding. The sandwich also helped establish the chain's practice of promoting a signature item as a recognizable icon alongside the restaurant's broader logo and characters.
The Quarter Pounder is another major McDonald's sandwich, but it uses a single larger beef patty. The Big Mac's defining feature is its two-patty, three-bun construction.