Whopper

The Whopper is the signature hamburger product sold by the international fast-food restaurant chain Burger King and its Australian franchise Hungry Jack's. Introduced in 1957, it has undergone several reformulations including resizing and bread changes. The burger is one of the best known products in the fast food industry; it is so well known that Burger King bills itself as the Home of the Whopper in its advertising and signage. Additionally, the company uses the name in its high-end concept, the BK Whopper Bar. Due to its place in the marketplace, the Whopper has prompted Burger King's competitors, mainly McDonald's and Wendy's, to try to develop similar products designed to compete with it.

The company markets several variants of the burger as well as other variants that are specifically tailored to meet local taste preferences or customs of the various regions and countries in which it does business. To promote continuing interest in the product, Burger King occasionally releases limited-time variants on the Whopper. As the signature product of the company, it is often at the center of advertising promotions, product tie-ins, and even corporate practical jokes and hoaxes. Some of the early twenty-first century advertising programs, particularly in Europe, have drawn criticism for cultural insensitivity or misogyny. Additionally, as the signature product in the company's portfolio, Burger King has registered many global trademarks to protect its investment in the product.