Marsha Simms, the carhop at Arnold's, appeared in 19 episodes of Happy Days, beginning with the Season 1 "Guess Who's Coming to Visit?". The part of Wendy was played in 18 of the episodes by Beatrice Colen; another girl named Marsha, possibly Marsha Simms, appears in the Season 9 episode "Tell-Tale Tart" (episode #21) played by Toni LeBel. Still another character named Marsha appears in the Season 8 episode of Laverne & Shirley titled "The Baby Show", who's played by Lynne Marie Stewart.
Marsha is a carhop at Arnold's Drive-In, whom, along with the buxom blonde carhop Wendy (Misty Rowe), often fall prey to the guys practical jokes, namely from Potsie and Ralph Malph. In her appearance in the episode "Richie's Flip Side", she negotiaties Arnold's conditions in allowing a radio station manager, Norman Bander (played by Jesse White) who's just hired Richie as a nightime DJ on his radio station, WZAZ, to broadcast from Arnold's Drive-In.