The heroes of Marvel Comics’ “The Avengers” fought their way across movie screens this summer, earning the highest opening weekend of all time. But these heroes weren’t the only victors. This summer’s other comic books brought to life, “The Dark Knight Rises” and “The Amazing Spider-Man,” were also released to huge financial success.

No longer nerdy outsiders, comic book fans are now part of mainstream entertainment and couldn’t be prouder.  Generation Y constitutes a significant part of the fandom, with half of “The Avengers”’ audience under the age of 25, and Comic-Con, the annual convention of all-things-comic-related, placing most of its attendees in the 16 to 34 age group.

A member of Generation Y and avid comic fan, Andrew Choi shares his interest with other students at New York University as treasurer of the Comic Book League, a group that meets weekly to discuss comics and assemble “The Comic Book League Presents,” a collection of comics made by group members and published at the end of each academic semester. While Choi says that the group’s size and demographics often change, he believes there is a commonality in how they discovered comic books.

“We grew up with the Saturday morning cartoons, and a lot of them in our generation were based off old comic books, like the old animated ‘Spider-Man’so it helps that we were introduced in a way that was easy to digest,” he said, “ I speak for a lot of our members, as I grew up I became more interested in the characters and then as I started picking up more issues, I became more interested in storylines.”

Though he believes that the more traditional superhero comics will always be popular, Choi has noticed that within the past few decades, a new type of fan has emerged, and attributes that change to the more serious comics of the late 1970s and early 1980s with the advent of the edgy, darker, grittier comics. “Now that’s what everyone goes for,” he said. “It’s created a little bit of a divide in comic book mentality.”

One characteristic unique to Generation Y though, is the acceptance of comic fans, “I think it’s become less stigmatic to be a nerd,” Choi said. “As a whole, especially in our generation, people have become more accepting.”

However, Rob Salkowitz, the author of “Comic-Con and the Business of Pop Culture,” finds that Generation Y has brought more change to comic book culture. “The notion of ‘comics culture’ has grown to encompass not just comic books and related superhero properties, but adjacent genres like sci-fi/fantasy and urban horror,” he said, “so Millennials are exposed to a broader range of possibilities for comics as a medium.”

Salkowitz has also seen a difference in the comic audience within this age group, “Gen Y has brought much-needed gender balance to Comic-Con and fandom in general,” he says.

Comic-Con has always been a major event for comic fans, and as it’s become even more popular it has broadened its range of programs. This year’s San Diego Comic-Con, the largest of the conventions, included a screening of the new television show “666 Park Avenue,” a panel with stars from “The Vampire Diaries,” and many similar events without a connection to comics.

Salkowitz draws a parallel between Generation Y’s familiarity with comics in different mediums and the expanded offerings at Comic-Con. “I think part of this has to do with a generational shift in the fan base from older (mostly male) fans who enjoy the characters and stories through the prism of ‘collecting comic books’ vs. younger people whose primary exposure to comic culture has been through movies, manga, TV shows, videogames and other media,” he says.

But he also believes it comes from the more recent inclusion of female fans, as well as the convention itself having “achieved a kind of critical mass where it is a media event in and of itself.”

One of last year’s New York Comic-Con attendees, New York University student Aliza Goldstein, 20, was drawn to the event more out of curiosity than any specific interest. “I just wanted to check it out. There weren’t any specific events or panels that I was looking at,” she says, “I was kind of there as a general participant in geek culture.”

Anyone looking for such an experience may find one similar at Forbidden Planet, a store just a few blocks away from New York University in Greenwich Village. Manager Jeff Ayers is hesitant to classify it as a comic store, instead referring to the spot as “a pop culture geek mecca.” and looking around, there is much more to Forbidden Planet than comic books. One wall displays the T-shirts available for sale, while below stand racks covered in toys and action figures based on yes, classic comic characters such as “Iron Man,” but alongside characters from the “Harry Potter” series and British television show “Doctor Who.”

“We have a Comic-Con in here everyday, it’s this eclectic mix of people. You could get into a conversation with anybody in an aisle and they’ll give you ten different perspectives on what they’re into,” Ayers says of the store.

As the manager of Forbidden Plant for the past 18 years, Ayers has seen the evolution of comic book culture, and has noticed a certain aspect in the mainstream crossover. “It’s not the shift in audience so much as the acceptance of that audience,” he says. “I remember like eight years ago or something like that turning to my best friend who grew up with me in the store and saying ‘everybody wants to be us right now.’”