10 Classic TV Series You Didn't Know Were Spinoffs
2. Happy Days (1974-1984) 
Spun off from: Love, American Style With the 1970s under way there was a resurgent interest in the music and culture of the 1950s. George Lucas burst onto the scene with American Graffiti, Grease was a hit on Broadway, and producer Garry Marshall launched a hit television sitcom that offered a nostalgic look back for those who grew up during the 50s.
Happy Days starred Ron Howard, best known as Opie from The Andy Griffith Show, as teenager Richie Cunningham. Tom Bosley played the traditional American father figure dispensing wisdom from his easy chair. Marion Ross played Richies mother and Anson Williams and Donny Most were cast as two of Richies best friends.
But the key to the success of the show was Henry Winkler, who played Arthur Fonzie Fonzarelli, a 1950s biker-type who lived in the apartment above the Cunninghams garage. Fonzie was cool. He was tough. He was a smooth operator. And beneath his leather jacket-clad exterior he had a heart of gold. Series creator Garry Marshall had wanted to get a show like Happy Days off the ground for some time, but couldnt sell it to a network. Thats where Love, American Style came in. It was an anthology series that ran from 1969 to 1974. His pilot script found a home. In February 1972 Love and the Happy Days starring Ron Howard, Marion Ross and Anson Williams aired on American television. It didnt take long for Happy Days to get a green light. Happy Days went on a successful ten year run, spawning seven spinoffs of its own, two of which were animated.