Leonard Hofstadter

The story of The Big Bang Theory follows the character Leonard Hofstadter and the crazy experience he has with this friends. Before becoming Sheldon's roommates, he received his Ph.D early in his life and now works at the same university as his current roommate. Along with Sheldon, Leonard also works with his other two friends Howard and Raj. Back at his apartment, he has found his new love interest, the girl next door, Penny.


Leonard Hofstadter

Sheldon Cooper

Sheldon Cooper is the other main character of the show and roommate of Leonard. Gifted with incredible intelligence, this often goes against him in the social world and peer-to-peer communication. He dispises any form of human comminucation or physical contact thought is very knowledgable in the field. Many who meet him often find him crazy inwhich Sheldon responds "I'm not crazy, my mother had me tested."
Sheldon Cooper

Penny

Penny is the girl who lives across the hallway within Leonard's and Sheldon's apartment building. She also joins the crew in their crazy activities though sometimes shows no interest in the many scientific side of the show. She has grown close to everyone in the show, mostly Leonard and often express she has deeper feelings for him later on. Penny provides the show with a stereotypical view on the "world of geeks" as she finds many of the stunts pulled off by the group nerdy and uninteresting.


Penny

Rajesh Koothrappali "Raj"

Raj is a cooworker and close friend of both Leonard and Sheldon. The most notable trait of Raj is his inability to talk to women. His phobia is so extreme that he will stop mid-sentence while talking when a female enters the room. Other than that, he is an extremely well accomplished astrophsicist who has made many new discoveries in the field such as a moom.


Rajesh Kootherrappali

Howard Wolowitz

The mechanical engineer of the group, Howard Wolowitz works with both Leonard and Sheldon at the university. He lives with his mother who he finds to be very annoying but yet can't get himself to leave her. Often creeping out Penny with his many advances, he believes he is the perfect ladies' man. In later season, he begins a relationship with his current girlfriend and eventually wife, Bernadette.
Howard Wolowitz

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