Marshall was inspired to create the iconic character of greaser Arthur Fonzarelli, better known as Fonzie, by his best friend at a camp called Greenkill, located in the Catskill Mountains in New York, where he worked at as a counselor when he was a teenager. Marshall says his friend Pete Wagner was the basis for Fonzie. "A cool, silent type with penetrating eyes," Marshall writes of Wagner. "Pete had the confidence, self-esteem, and 'cool' quality I admired and wanted to cultivate for myself. He told me the best book you could read was 'Catcher in the Rye,' and he was right." At Greenkill, the staff found out Marshall knew some Yiddish and gave him all the Jewish campers. Marshall says he would conduct weekly services for them which he would make up off the top of his head.

Ron Howard (l.) as Richie Cunningham and Henry Winkler (r.) as Arthur Fonzarelli on the TV show 'Happy Days'