"The Fault in Our Stars," this month's resounding box-office success, has been marked as the triumphant return of the "tear-jerker" genre to the cinema. But Esther Earl, who inspired John Green's bestselling Young-Adult book-turned-movie, would not want you to cry, but rather to celebrate friendship and life.

When asked what message she would like to share with the world, it was: "tell the people you love that you love them."

Like Hazel, the fictional character she inspired, 16-year old Esther fought thyroid cancer. Unlike Hazel, she found her strength not in a romantic relationship, but in a community of teenagers who spent countless hours online sharing a common love for Harry Potter, Spelling Bees, and "all things nerdy."

Esther's greatest wish, granted to her by the Make-A-Wish Foundation, was to meet her online friends face-to-face.

The online group that was so meaningful to Esther is "Nerdfighteria," now comprising of several millions of young people who have gathered around the "Vlogbrothers"--the name of the successful YouTube video-blog channel of author John Green and his brother Hank--but, have come to be a significant online phenomenon of their own.

The hype around "The Fault in Our Stars" being a record-breaking movie, even before its release, is at least partially the work of avid Nerdfighters. Social media analysts have caught on to the online community's role in driving the movie's success, asking about the "strategic takeaways" that those wishing to build an audience can learn from the Nerdfighters.

Having conducted more than three years of research with Nerdfighters, I'm frustrated when this group is framed as simply a movie-going audience. Instead, Nerdfighters should be acknowledged as a self-standing online community, meaningful both as a source of friendship and support for young people, and as a site for civic learning and action. Nerdfighters simply call it "decreasing world suck."

Nerdfighters are a creative and unorthodox bunch, as likely to be playing a hand-made ukulele as they are to be shooting the next installment of their collective video-blog on YouTube.

Unlike what the media coverage may suggest, Nerdfighters aren't just "fans of John Green" (or his brother Hank, who for Nerdfighters holds the same celebrity status). The Green brothers are only one common ground uniting Nerdfighters.

Rather, Nerdfighteria is a place where young people meet like-minded others, and can proudly let their "inner nerd" shine. It is a place where they can share their most intimate worries and concerns. Just as Esther shared her struggles with cancer, other Nerdfighters share the problems they face, such as their parents' divorce, battling depression, or uncertainties around their sexual identities.

While many have come to acknowledge that online communities can provide social support for young people, they may be surprised that Nerdfighteria is also a place where young people come to see themselves as civic actors.

As part of my research, I've seen Nerdfighters learning about social issues through VlogBrothers' humorous, fast-paced yet highly informative videos. I've seen them modeling the VlogBrothers by becoming YouTube video producers themselves, sometimes using this forum for expression of political views. And, I've heard Nerdfighters discussing political issues with others in the community through YouTube comments or extended conversations on Skype.

Their actions have had tangible real-world effects. Nerdfighters have been the largest community of lenders on Kiva.org, a non-profit organization granting loans to people without access to traditional banking systems.

Every year, Nerdfighters promote charities and non-profit organizations by creating YouTube videos about them, and encouraging donations.

In 2013, this endeavor raised more than $850,000 to the "Foundation to Decrease World Suck," a nonprofit created by the VlogBrothers, benefiting a variety of causes and organizations. Nerdfighters have accomplished these goals precisely by building on the cultural and social bonds that tie the community together.

One of the non-profits that benefited from the Nerdfighters' civic work is This Star Won't Go Out, a foundation started by Esther Earl's parents to provide funds and assistance to families of children with cancer.

Esther died of cancer at 16. She didn't read the book or see the movie inspired by her story. But, the people she loved -- her online community of friends -- are continuing her legacy by making the world a better place, one nerd at a time.