The television series "Mork & Mindy," starring Robin Williams, was a spin-off of the popular sitcom "Happy Days." In "Happy Days," Robin Williams made a guest appearance as an alien character named Mork from the planet Ork in the episode titled "My Favorite Orkan," which aired in 1978. Williams' performance as Mork was well-received by the audience, leading to the creation of the spin-off series "Mork & Mindy." "Mork & Mindy" followed the adventures of Mork, who comes to Earth and lives with a young woman named Mindy McConnell, played by Pam Dawber. The series ran from 1978 to 1982 and further showcased Robin Williams' comedic talents and improvisational skills.