There’s no denying that CBS' The Big Bang Theory has come a long way. Currently in its 11th season, the series usually resides at the top of the weekly ratings of the Broadcast networks, and over the course of its run has made the words "nerd" and "geek" far more acceptable to the mainstream audience than ever been. And why shouldn’t it, when you consider that, whatever it is that gets our geek on, makes all of us geeks? And we’re not just limiting it to sci-fi shows like Star Trek. It could be reality shows, a certain band and, yes, even sports. Think about it: fans attending a football game, who may have painted themselves different colors and are waving huge foam fingers around in support of their favorite team, aren’t really all that different from cosplayers hanging out with fellow fans at Comic-Cons. We have met the nerd, and he is us!

And I met the king of the nerds, Sheldon Cooper (or, more precisely, actor Jim Parsons), during the early days of The Big Bang Theory back in 2007. The show was already proving itself to be a hit and had become a favorite of critics and the audience. Almost immediately, Jim, as well as co-stars Johnny Galecki (Leonard Hofstader), no stranger to sitcom success thanks to Roseanne; Kaley Cuoco (Penny), Simon Helberg (Howard Wolowitz), and Kunal Nayyar (Raj Koothrappali) found themselves elevated to a new level of stardom. Here, we take a look back at all Jim told us in a never-before-released interview where he really painted a vivid picture as to how he transforms into the one and only, Sheldon Cooper.

Learning Sheldon's lines, as you would imagine, wasn't always easy.

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For Jim, the challenges early on came from trying to humanize Sheldon, who seemed in many ways the most alien among the characters. In fact, it's what makes the new show, Young Sheldon, so fascinating, because you're left wondering how that little boy grew up to become the more sheltered and anti-social Sheldon we were introduced to on The Big Bang Theory. And then, there was the memorization of all of that dialogue that in some ways was like a foreign language to Jim.

"That has been the most challenging," he told me. "I don’t mean it’s been backbreaking, because I tend to enjoy memorizing lines. My mother and sister are teachers, so I have a big scholastic streak in me. I enjoy studying when I like the topic, and I enjoy reading lines, and I enjoy making flashcards and looking up words to make sure I understand them and how to pronounce them. Talk about geeky! But at the same time, there are complications from topics I don’t understand at first glance, and trying to make emotional connections to the conversation in which Sheldon is throwing these terms around. To make an emotional point, he'll use these… words.

"The other thing that’s creeping in a little bit," Jim adds, "and this is a challenge, but a fun one for me, is that Sheldon can be a pain in the a– sometimes. At the same time, I try not to make too much of keeping him 'likable.' That’s not really my concern. One, that's in the writing, and, two, I don't think it always matters. I think it’s okay to have a character who the audience gets a little irritated at sometimes. That's just fine. But a couple of times I have to take a couple of swats at it, which I guess is why we have rehearsal and it’s part of being an actor. But there have been comments or situations they’ve written Sheldon into where you say, 'You know what? That’s just plain b–hy when I do that.' There’s a factualness about Sheldon, and that can be a challenge, to know that Sheldon is just sticking to the facts and not necessarily socially commenting on the situation."

The arrival of Penny threw off Sheldon's routine big time.

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Early on, that situation became more complicated with the arrival of Penny, who, despite living across the hall, threw Sheldon’s routine out of whack, which became a problem for quite a while.

"In response," Jim says, "Sheldon is trying to look at it scientifically. Despite his brilliant mind, he's like a child in terms of his response to the routine being interfered with, and, also like a child, sometimes he has to be guided. From the beginning, that’s been a part of his relationship with Leonard. And Leonard is just more cognizant of some social niceties, and isn't afraid and is willing to reach out and throw Sheldon a bit of advice, or cover for him if need be."

One of the things viewers often wondered was whether or not the way Sheldon saw the world actually interfered with the possibility of the character changing and evolving. Obviously, over the course of the past 11 years we've seen him go through some changes — and some of them pretty significant (relatively speaking) — but in those early days, no one could be sure.

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"Without being with the writers while they’re coming up with these things, I can’t say for sure," he offered. "But I think that’s unavoidable for the longevity of the show and the interest of everyone working on it. I would imagine it's somewhat inevitable that there’s going to be some change and growth in there. Each new episode brings new opportunities to introduce new people to these characters, and that obviously includes Sheldon. One question is, will Sheldon find love? Because that’s a real obvious one, and that may be exactly what happens. But taking that as an example, love is something that could rock his world and change the foundation he bases his ideas on. And that would be really lovely. But at the same time, this is a comedy and we better keep people laughing."

Jim formed a connection with Kaley Cuoco that plays well on-camera.

Of course, Mayim Bialik was introduced two years in as Amy Farrah Fowler and their relationship has had a huge impact on Sheldon, but in year one, nobody knew. Although Jim, for his part, sensed right away, that despite the fact they would snipe at each other, Penny would have an influence on Sheldon as well in terms of opening up his world.

"I love the relationship she and I have fumbled upon just as actors working together," said Jim regarding Kaley. "And that the writers have injected life into it and embraced what they've seen in us. I love the little interactions they've given Penny and Sheldon. They're not always overly-involved dialogue wise, there are some that are just a couple of comments or exchanges between the two of them where both of them are standing there stumped. Just kind of looking at each other, like, 'What?' I love the impasses they come to; I think it’s just beautiful. But whatever is there between them, it's a beautifully mysterious question of where it comes from, because it’s not an attraction, there's no flirtation. There's a weird kind of definition of what connects them. I guess Leonard's interest in her has something to do with it, or the physical proximity of her apartment, but whatever it is, they've been allowed to develop some odd things, which are lovely."

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He points to an episode where Sheldon gets sick and Penny, at the end, actually takes care of him. "That was obviously a situation that's in a comedy," he said, "but if you've been to college or if you've lived in an apartment, just any sort of forced communal living, those are the exact events that happen. I found it very true to life where suddenly Penny was taking care of Sheldon, the sick neighbor, and that part of the story is in no way far-fetched in the moment. It's a defining moment that happens between people in a relationship that a past is built on; those weird, almost accidental events that add up to a life you've lived together. And whether a long-lasting friendship is based on it is beside the point."

Mentioned to him was that, especially in those early days, there was something about Sheldon that was reminiscent of the fastidious Felix Unger character in the Classic TV series The Odd Couple. "From what little I’ve watched of The Odd Couple, I couldn’t agree more," replied Jim. "And there is a huge commonality in that their way is the only way, or their way is the best way. At the very least, their way is the only way they know, and their way is the only way that they can deal. Which I guess everyone is like to a certain degree. This is just a magnified version. Sometimes it’s irritating, and sometimes you get a look in and think, 'Oh, that’s just their human way.'"

There are a couple of things Jim himself really geeks out over.

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Given the nature of The Big Bang Theory, there was also a question of what it was in life that appealed to Jim’s geeky side. His response was pretty immediate.

"Simon and I did some odd pop culture geek thing online," he said, "and I only bring that up, because it made me really think about it. One of the things I put in there, and I sort of mentioned this already, was learning lines and looking at words and definitions and pronunciations. Maybe a writer would appreciate it, but I tend to be geeky about getting the line exactly right as it's written. And the reason it comes off geeky — and it could be a little irritating — is I will stop mid-sentence as opposed to trying to carry on and save the moment, because I don't want to get the line wrong. I'm trying to get better with that. [Co-creator/executive producer] Chuck Lorre once yelled at me, 'You already have the part!' I hear, you Chuck. I understand. But I'm a little OCD about this.

"I was also a huge radio geek — I don't know why," he continued. "I was talking to my sister the other day. We had a Great Aunt in Texas, who we remember now, but when we were children she always had talk radio on in her kitchen, or in her bedroom when she was going to sleep, or in the car. I remember thinking it was odd. But then, as I've gotten older, I had thought about that as I was forming this habit. Julie, my sister, said, 'That's what Lala used to do,' and I'm, like, 'Oh my God, you're right!' It's something genetic. How weird.' And it could relate quite literally to my passion for words and learning lines. I'm obviously a verbal geek."

And the connection between character and actor gets even stronger.

The Big Bang Theory airs Thursday nights on CBS.