The voice of Scooby’s human pal Shaggy was provided by “American Top 40″ radio personality Casey Kasem… Scrappy-Doo, a puppyish nephew of Scooby-Doo, appeared in some episodes of the cartoon; Scrappy is famously disliked by many devoted Scooby fans.
The show was first known as Mysteries Five and later changed to Who’s Scared? The show was then presented to the top CBS management and president Frank Stanton as a new Saturday morning cartoon for the fall of 1969.
There was one problem: the artwork was very frightening which led Stanton to reject the show. Silverman immediately flew back to Los Angeles that night. While listening on the earphones on the flight back, Silverman was relaxing to Frank Sinatra singing Strangers in the Night. The phrase ‘Scooby-Dooby-Doo’ struck Silverman so much that he went back and said ‘We’ll call the show Scooby-Doo, Where Are You? and we’ll make the dog the star of the show.’ And with those words Scooby-Doo was created with the other characters supporting him.