Johnny Galecki

Johnny Galecki is an American actor. He rose to fame as David Healy on ABC's Roseanne (1992-1997). Galecki reprised the role on the Roseanne revival (2018) and its spinoff The Conners (2018-2019). He is best known for playing Leonard Hofstadter on The Big Bang Theory (2007-2019). Galecki earned an Emmy Award nomination for his performance on the CBS sitcom and became one of the highest paid actors on TV. He also has appeared in the films National Lampoon's Christmas Vacation (1989), I Know What You Did Last Summer (1997), In Time (2011) and Rings (2017).
"The Comet Polarization" - Pictured: Howard Wolowitz (Simon Helberg), Leonard Hofstadter (Johnny Galecki), Rajesh Koothrappali (Kunal Nayyar), Penny (Kaley Cuoco), Sheldon Cooper (Jim Parsons) and Amy Farrah Fowler (Mayim Bialik). Sheldon's comic book store experience changes when writer Neil Gaiman puts Stuart's store on the map. Also, Koothrappali takes credit for Penny's astronomical discovery and friendships are threatened, on THE BIG BANG THEORY, Thursday, April 19 (8:00-8:31 PM, ET/PT), on the CBS Television Network. Photo: Jordin Althaus/Warner Bros. Entertainment Inc. © 2018 WBEI. All rights reserved.
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LOS ANGELES - SEPTEMBER 20: "The Hot Tub Contamination" -- Pictured: Penny (Kaley Cuoco) and Leonard Hofstadter (Johnny Galecki). Leonard and Penny must separate a quarreling Sheldon and Amy when their cohabitation does not go as planned, and Sheldon threatens to break off their relationship when Amy refuses to adhere to the bathroom schedule. Also, Howard and Bernadette find unexpected guests at their house when they decide to stay home from a planned vacation, on THE BIG BANG THEORY, Monday, Oct. 17 (8:00-8:31 PM, ET/PT), on the CBS Television Network. (Photo by Sonja Flemming/CBS via Getty Images)
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