Scott Vincent James Baio is an American actor. He is known for playing Chachi Arcola on the sitcom
Happy Days (1977â1984) and its spin-off
Joanie Loves Chachi (1982â1983), the title character on the sitcom
Charles in Charge (1984â1990), Dr. Jack Stewart in the medical-mystery-drama series
Diagnosis: Murder (1993â1995), and the titular role of the musical film
Bugsy Malone (1976), his onscreen debut. Baio has guest-starred on various television programs, appeared in several independent films, and starred on the Nickelodeon sitcom
See Dad Run (2012â2015).