The segment "Love and the Happy Days" was an unsold pilot. The success of American Graffiti (1973) convinced ABC to pick it up as the series Happy Days (1974).
Ron Howard (Richie), Marion Ross (Mrs. Cunningham), and Anson Williams (Potsie) reprised their roles from this 1972 episode in the Happy Days series in 1974.
Reportedly, George Lucas decided to cast Ron Howard in American Graffiti (1973) after seeing him in this episode.
If 'Love and Happy Days' counts as a Happy Days' episode, it is the only one that Tom Bosley and Henry Winkler don't appear in. Howard Cunningham is played by Harold Gould and there is no 'Fonzie' character.
Richie wears a leather jacket similar to the one Fonzie wore in Happy Days except Richie's jacket has flap pockets.