Chain: McDonald's
Introduced: 1967 (in Pittsburgh), 1968 (nationwide) 

It's the first thing you think of when you hear the name "McDonald's." The Big Mac has become a pop culture icon, and if we learned anything from Pulp Fiction, it's that Europe also respects the sandwich. And yes, it does technically count as an innovation; the first McDonald's opened in 1940, but the Big Mac wasn't introduced nationwide until 1968 (and not a moment too soon). All other fast food burgers live in the Big Mac's shadow.