The show originally centered on five characters living in Pasadena, California: Leonard Hofstadter ( Johnny Galecki) and Sheldon Cooper ( Jim Parsons), both physicists at Caltech, who share an apartment Penny ( Kaley Cuoco), a waitress and aspiring actress who lives across the hall and Leonard and Sheldon's similarly geeky and socially awkward friends and coworkers, aerospace engineer Howard Wolowitz ( Simon Helberg) and astrophysicist Raj Koothrappali ( Kunal Nayyar). It aired on CBS from September 24, 2007, to May 16, 2019, running for 12 seasons and 279 episodes.
The Big Bang Theory is an American television sitcom created by Chuck Lorre and Bill Prady, both of whom served as executive producers and head writers on the series, along with Steven Molaro.
