The Big Mac is one of two signature sandwiches (the other being the Quarter Pounder) made by McDonald's, consisting of (as per its famous advertising jingle, introduced in 1974) "Two all beef patties, special sauce, lettuce, cheese, pickles, onions, on a sesame seed bun." It was developed in Uniontown, Pennsylvania by Jim Delligatti, one of Ray Kroc's earliest franchisees, in 1967. The Big Mac debuted at Delligatti's restaurant at a selling price of 45 cents. It was created to compete with a similar Big Boy sandwich. It was introduced nationwide in 1968. It consists of two 1.6 oz (45.4 g) beef patties. The Big Mac's bun is separated into three layers. In Canadian McDonald's restaurants, the Double Big Mac, as its name implies, doubles the number of patties to four. In India (where consumption of beef is prohibited on religious grounds), this item is modified as the Chicken Maharajah Mac (which uses chicken instead of beef) and a vegetarian version, the Veg Maharajah Mac.
It is unknown to most what the "special sauce" on a Big Mac actually is, though some think it is simply thousand island dressing. Big Mac Sauce is delivered to McDonald's restaurants in sealed canisters designed by Sealright, which are dispensed on burgers with tools that are similar to caulking guns.