For years, movies and TV shows depicted nerds as side characters. They were the hero's classmate or the comic relief.  Then nerds became cool, and when The Big Bang Theory broadcast its first episode in 2007, nerds were finally the stars of the show.

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There are plenty of quirks that define nerds. These apply to most of the main characters in The Big Bang Theory: an obsession with sci-fi and superheroes; highly intelligent with jobs in specialized scientific fields; being a know-it-all; and (in the early seasons at least) difficulty relating to people of the opposite sex. What other quirks do The Big Bang Theory characters have? What sets them apart from one another (and from other TV nerds)?

Leonard

Leonard sitting down and smiling in TBBT.

Best Quirk: Attractiveness

Before most of the characters settled down with long-term partners, Leonard was the member of the group who had the most luck with women. He had liaisons with, among others, Dr. Plimpton, Alice, Leslie Winkle, Stephanie, and Priya. Some fans think that Leonard’s luck with women was primarily due to his eyebrows. Fans agree that Leonard Hofstadter had very expressive eyebrows. In the episode ‘The Decoupling Fluctuation,’ Penny couldn't dump Leonard because of his "puppy dog eyes."

Worst Quirk: Disrespect Of Privacy

Leonard wasn't above using underhanded techniques to impress women, though. He once told Penny that he was "the king of husbands" because he knew so much about her. It turned out the reason he knew so much (like the fact she hated the orange negligee he bought her) wasn't because Leonard listened to what she said, but because he read her diary.

Raj

Raj presenting at the planetarium in The Big Bang Theory

Best Quirk: Understanding Of Others’ Anxieties

Raj’s biggest quirk throughout the earlier seasons was his inability to talk to women. His selective mutism meant he was literally incapable of getting the words out. Having his anxiety rule his life in such a big way ensured that he was more sympathetic to other characters who had similar issues. He thought of a perfect date for shy Lucy: an evening in a library communicating by text message. This date idea demonstrated Raj's thoughtfulness.

Worst Quirk: Drinking Brings Out His Worst Qualities

His inability to speak around women also brings out Raj's worst quirk. One of the saddest things about Raj on The Big Bang Theory is that he would get drunk to overcome this issue. While it may have freed his tongue, he was a sexist and belligerent drunk, and it rarely worked out well for him. It put a lot of women off because it turns out that women aren't impressed with crude misogynists.

Howard

Howard Wolowitz smiling in The Big Bang Theory

Best Quirk: Imagination And Creativity

Howard is the most imaginative member of the group, which is reflected in his unique clothing style. This sense of creativity explains why he loves doing conjuring tricks. While the rest of the gang lack hobbies outside of work and comic and movie fandom, Howard has a skill that takes many hours to master. It’s a shame for Howard that whenever he showcases this talent to his friends, they're rarely impressed.

Worst Quirk: Creepiness Around Women

Before he settled down with Bernadette, Howard put considerable time and effort into mastering underhanded pickup skills. No cheap technique was too low for Howard. He dressed as a goth, allowed women to operate space machinery, and wore an eyepatch. The worst example of his excessive creepiness was when he used military surveillance and robot cameras to locate and infiltrate the America's Next Top Model house.

Penny

Penny raises her eyebrows confidently in The Big Bang Theory

Best Quirk: Generosity And Inclusivity

Penny loves to party and is inclusive in her invitations. She invited the guys to her Halloween party in Season One without worrying that they might be too geeky or not fit in with her friends. Her accepting nature is why she and the other characters became good friends over the course of twelve seasons despite their unlikely beginnings.

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Worst Quirk: Irresponsible Behavior When Drunk

Penny's drinking habits calmed down as she matured, but she frequently exhibited worrying behavior around alcohol. She drank wine out of a measuring jug when she didn't have any clean glasses and sipped neat rum from an eggnog carton. When she played Twister with Amy and Bernadette, she interpreted “right hand on red” as an instruction to drink red wine and minutes later passed out on the Twister mat in an alcoholic stupor, only rousing when Bernadette said, “We’re out of wine!”

Sheldon

Sheldon Cooper sitting down and looking relaxed in The Big Bang Theory

Best Quirk: Honesty

Sheldon's entire personality could be described as a collection of quirks, many of which would make him an infuriating person to spend time with in real life. He does, however, have some redeeming qualities, such as his honesty. Sheldon is terrible at lying on The Big Bang Theory and hates keeping secrets. As this also includes little white lies, it’s not difficult for his friends to find out what he really thinks about something. He will come right out and tell them.

Worst Quirk: Selfishness

His worst trait is his inability to empathize or to accommodate anybody else’s needs. Whatever happens, Sheldon will only ever consider how it affects him personally. He will always put his own interests first. The worst example of this is when, during their experiment to survive in harsh conditions, he left Raj behind to be attacked by rats while ensuring his escape.

Bernadette

Bernadette at her office smiling in TBBT

Best Quirk: Forthrightness

Bernadette has a forthright nature and isn't afraid to speak her mind. In 'The Conjugal Conjecture,' instead of greeting Penny's walk down the aisle with respectful silence, several characters make comic asides to one another. Bernadette, who is conducting the ceremony, sharply barks out that she’s “not going to put up with all the side chatter, so let’s knock it off." It was the right call and echoed what many viewers were thinking.

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Worst Quirk: Bullying

However, Bernadette's bossy nature and fierce temper mean that she is not always easy to get along with, and many people find her scary. When Penny attends a job interview, she and Bernadette’s boss, Dan, bond over their shared fear of Bernadette. “I thought it was just me,” Dan says. “Everyone thinks she’s so nice with that squeaky little voice.” “I know,” Penny agrees. “But she’s kind of a bully.”

Amy

Amy Farrah Fowler smiling on The Big Bang Theory

Best Quirk: Accommodating

Amy’s accommodating nature was the reason why her and Sheldon’s relationship progressed as much as it did. Most women would have thrown in the towel when confronted with the challenge of dating Sheldon, but Amy was always mindful of Sheldon’s unusual personality traits. She accepted his need for routine and his discomfort with physical contact, and she handled them as best she could. She even thought that signing a 31-page relationship agreement was “romantic.”

Worst Quirk: Neediness

Amy’s worst quirk was that she often came across as too needy. She put Sheldon’s needs above her own even when it hurt her to do this. She freaked Penny out by lavishing her with expensive gifts and inappropriate comments. She gave Penny a painting depicting the two of them together. Penny hated it and wasn’t pleased to hear that Amy originally had the artist paint the pair of them naked.

Stuart

Closeup of Stuart Bloom in his comic book shop

Best Quirk: Artistic Abilities

Not part of the core set of friends, Stuart's role on The Big Bang Theory was nonsensical sometimes but nonetheless important. He was, for much of the series, the owner of the gang’s favorite comic book store, which is a pretty quirky profession. Stuart's best quirk, though, was the fact he was an artist. He studied at the Rhode Island School of Design and once charmed Penny into having a date with him by sketching her portrait.

Worst Quirk: Low Self-Esteem

Stuart’s plans for Valentine’s Day were “hiding all the sharp objects.” Another time. Once, he dated a girl he met at a comic convention who he described as “horrible” just because he didn’t want to be alone. As Stuart became more integrated with the group, it would have been nice if he could have learned to like himself a bit more.

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