Johnny Galecki
John Mark Galecki is an American actor. He played Leonard Hofstadter in the CBS sitcom The Big Bang Theory (2007–2019) and David Healy in the ABC sitcom Roseanne (1992–1997; 2018).
John Mark Galecki is an American actor. He played Leonard Hofstadter in the CBS sitcom The Big Bang Theory (2007–2019) and David Healy in the ABC sitcom Roseanne (1992–1997; 2018).