Football rules, uniforms, helmets and protective gear have changed a lot over the years. Keystone-France/Gamma-Keystone via Getty Images hide caption

itoggle caption Keystone-France/Gamma-Keystone via Getty Images

The founder and chairman of Shake Shack, Danny Meyer, visits the floor of the New York Stock Exchange. Spencer Platt/Getty Images hide caption

itoggle caption Spencer Platt/Getty Images

The defending champion and favorite remains the chicken wing. But underdog snacks like the carrot are trying to elbow their way into the competition. Leif Parsons for NPR; Source: whologwhy/Flickr hide caption

itoggle caption Leif Parsons for NPR; Source: whologwhy/Flickr

Think of human relationships as entanglements. How do they bind you; how do they reveal who you really are? Daniel Horowitz for NPR hide caption

itoggle caption Daniel Horowitz for NPR

Friday, DeMarcus Cousins of the Sacramento Kings reminded sports journalist Clay Travis that his five-year guarantee — that Cousins would be arrested — had expired. Thearon W. Henderson/Getty Images hide caption

itoggle caption Thearon W. Henderson/Getty Images

Secretary of State John Kerry greets new Saudi King Salman in Riyadh on Tuesday. the city of Boston fined Kerry $50 on Thursday for failing to clear his sidewalk after this week's massive snowstorm. Carolyn Kaster/AP hide caption

itoggle caption Carolyn Kaster/AP