The burger business is all about share of stomach. There are only so many ways you can innovate when it comes to a hamburger, so copying competitors' ideas is standard practice. Take the Big Mac, which was launched in 1968 as McDonald's answer to the Whopper. Burger King introduced the Whopper in 1957 when, after realizing it couldn't compete with McDonald's 15 cent hamburger, it decided the solution was to sell a bigger burger for 37 cents. Burger King declared all-out war in 1982 by launching an advertising campaign that claimed customers preferred the Whopper to McDonald's and Wendy's. Both chains countered by suing for false and misleading advertising. In 1997, the Home of the Whopper again took on the Golden Arches -- this time its fries with the tagline "the taste that beats McDonald's." McDonald's struck back with its own advertising campaign.
The heated rivalry cooled as Burger King suffered a revolving door of CEOs and owners, which helped McDonald's gain more ground. In 2011, for the first time ever, Wendy's surpassed Burger King to become the No. 2 burger chain by sales. "In America, McDonald's has won," says Andrew Smith, who teaches food history at the New School. But don't count Burger King out just yet: In February the chain got into the latest fast food battle, Coffee Wars, when it announced a line of coffee-based drinks like lattes through a partnership with Starbucks' (SBUX, Fortune 500) Seattle's Best Coffee