"The Big Bang Theory" features a group of socially awkward scientists and their interactions. The main characters include Sheldon Cooper, a genius physicist with a lack of social skills; Leonard Hofstadter, an experimental physicist who often acts as Sheldon's roommate and friend; and Penny, an aspiring actress and waitress who lives across the hall from them. Other notable characters are Howard Wolowitz, an aerospace engineer known for his quirky fashion sense, and Rajesh Koothrappali, an astrophysicist who initially struggles with speaking to women. Together, they navigate friendships, relationships, and the challenges of their scientific careers.