The Big Bang Theory has educated and entertained millions since 2007. Now, nearly three hundred episodes and twelve years later, the beloved CBS series has come to an end. We've watched the awkward scientists take on life as they each grew in their fields and their personal lives, including their relationships.

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Everyone rooted for Leonard (Johnny Galecki) and Penny (Kaley Cuoco) to finally get together (which they did), and for Sheldon (Jim Parsons) to take each big step with Amy (Mayim Bialik), even if it took eons longer than a traditional relationship. In any case, here are the best couples to come out of The Big Bang Theory, and others we weren't so interested in.

NO: Kurt & Penny

Kurt (Brian Patrick Wade) was a complete jerk, one that Penny was with at the series' very beginning. When Penny sends Sheldon and Leonard to retrieve her TV from him, Kurt steals their pants instead. Penny also generously paid Kurt's fines when he was arrested and he never repaid her; at least, until Leonard convinced him to. The guy was a creep, and Penny's probably as glad as we are that this relationship never went anywhere.

BEST: Stuart & Denise

Comic-bookstore owner Stuart (Kevin Sussman) recently began dating Denise (Lauren Lapkus), a comic book aficionado that even has Sheldon's stamp of approval. Stuart over the years has struggled financially and has gone into bouts of depression, some instances of which have been cited and turned into a portion of the show's humor.

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Stuart is often overlooked (part of a running gag), but it's nice to see that the lonely store owner may get his own sliver of happiness in the end, which makes this relationship a favorite (yet not necessarily at the forefront).

NO: Leonard & Priya

Priya helps Leonard as he fumbles around without his glasses in TBBT

Remember when Leonard was dating Raj's sister, Priya (Aarti Mann)? The two dated for a little while, but no one was ever really into it. Leonard was always supposed to be with Penny, so we knew his relationship with Priya would never last. The relationship never really had a chance; Priya seemed uninterested in taking any significant steps.

Yet, they did maintain a long-distance relationship when she returned to India, up until they both admitted to having mutual indiscretions, which seemed to end their relationship. Well, we kind of saw that one coming.

BEST: Raj & Emily

Emily sitting next to Raj in The Big Bang Theory

Emily (Laura Spencer) was the redheaded dermatologist that began dating Raj when she found him through a dating site and sent him a message. Raj appears to have the hardest time of the group finding anything permanent in his love life, but while he was with Emily, we had some promising moments, making their relationship memorable.

She was obsessed with horror movies and had a thing for cemeteries but their relationship simply wasn't meant to be, especially since Raj was dating her and an aspiring screenwriter named Claire at the time, breaking up with them both.

BEST: Penny & Zack

Big Bang Theory Penny Zack drinking wine

Like Leonard and Priya, we knew this wouldn't last, but we didn't mind it as much. Zack (Brian Thomas Smith) is kind but dimwitted, something Penny doesn't appear too tolerant of, having been with Leonard. Zack and Penny were on-again, off-again and were even married once (something they were both unaware of), much to Leonard's horror. Zack was more of a casual conquest of Penny's than anything else, making this less of a memorable relationship to come out of the show.

BEST: Howard & Bernadette

Okay, Howard and Bernadette's (Melissa Rauch) relationship is a little odd. Bernadette, though tiny, has a reputation for being too aggressive at times, making her scary and intimidating. Howard sometimes seems scared of his wife (honestly though, everyone's a little terrified of Bernadette) but we can't deny that they love one another. They were the first to get married on the show and have stayed committed to one another, something we love to see.

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Considering Howard's tendency to get a little preoccupied and Bernadette being more on the domineering side, they balance each other out and it seems to flow well. Not to mention the two together are hilarious, making them one of the couples we loved watching the most.

NO: Mary Cooper & Alfred Hofstadter

Sheldon's mother and Leonard's father strike up a friendly bond rather quickly, which disturbs their respective children. When they disappear into a hotel for the night, it is assumed the two hooked up, though the couple denies it. It was said that they planned on seeing one another in the future, but we never got to really see the extent of that play out.

While it would be weird to have the parents of two of the main characters get together, the two made it seem natural and easygoing, implying a promising relationship. Knowing Sheldon though, he'd probably never let it last. Obviously, the writers didn't consider this promising, so we won't read too much into it, either.

BEST: Sheldon & Amy

Amy and Sheldon in the big bang theory

When Raj (Kunal Nayyar) and Howard (Simon Helberg) created a profile for Sheldon on an online dating site, the last thing they expected was to find Amy Farrah Fowler, Sheldon's perfect match. She and Sheldon shared so many common interests, it was obvious they would be great together.

Although it took much, much longer for them than most couples to make certain commitments, like living together or marriage (mostly because of Sheldon's nitpicky ways), they did get married and even won a Nobel Prize together. Talk about accomplishing something as a couple; therefore we love Sheldon and Amy!

NO: Sheldon & Beverly Hofstadter

Sheldon and Beverly sing Anyway You Want It

From day one, Sheldon and Beverly (Christine Baranski) struck up a strong rapport and seem to enjoy each other's company. For Beverly to enjoy anyone's companionship is a ceremonious and miraculous feat, one that Sheldon acknowledges and revels in, much to Leonard's consternation.

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At one point in the series, the two even shared a brief kiss, which thankfully Leonard was not privy to. While we're still cringing at that vivid image, we're glad that this incident never turned into anything. In fact, we'd rather forget.

BEST: Leonard & Penny

Leonard and Penny talk over wine on the Big Bang Theory

The on-again, off-again couple tortured audiences for years, wondering if the two would ever permanently end up together. They finally eloped, and as we saw in the series' finale, are starting a family together. The two couldn't be more opposite; Leonard a Star Wars obsessed scientist from New Jersey, and Penny, an aspiring actress turned pharmaceutical sales representative from Nebraska. Yet, the two genuinely love each other, having come a long way and made audiences happy with their union, making them one of the show's best couples.

In reruns, we'll get to see all these relationships play out over and over again, as many times as we like. As we bid farewell to this modern classic of a sitcom, we'll remember the best couples and forget the worst. Bazinga!

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