The show is primarily centered on five characters living in Pasadena, California: Leonard Hofstadter and Sheldon Cooper, both physicists at Caltech, who share an apartment; Penny, a waitress and aspiring actress who later becomes a pharmaceutical representative and who lives across the hall; and Leonard and Sheldon 's similarly geeky and socially awkward friends and co-workers, aerospace engineer Howard Wolowitz and astrophysicist Raj Koothrappali. The geekiness and intellect of the four men are contrasted for comic effect with Penny 's social skills and common sense.
where do they live in big bang theory
Pasadena, California