You know you've really become famous when your name becomes an adjective, as in "an Ed McMahon check," but the big man with the big laugh was famous even before he began handing out giant checks for Publisher's Clearing House.
McMahon put his mark on America as the most recognized sidekick in television history, serving as the straight man to the Tonight Show's Johnny Carson for 30 years. His outsized voice was pitched perfectly for the show's iconic introduction, "Heeeere's Johnny!" and his deep, heartfelt laughter at Carson's clowning earned him the nickname "The Human Laugh Track."
Before he began his television career, McMahon was a Marine Corps fighter pilot. McMahon dropped out of Boston College in 1943, joined the Marine Corps and was trained to fly Corsairs. McMahon never made it to World War II; the Marines retained him after flight school to be an instructor. In 1945 he had just received orders to a carrier squadron in the Pacific when the war ended.