More than an hour before the doors open at the Anaheim Convention Center, there's already a line that stretches from the entrance, past a nearby Hilton, around a water fountain, through a palm-tree lined promenade, and all the way to the driveway's entrance. Security guards in yellow shirts have begun packing people into neat zig-zag rows so that they do not spill out onto the street. "I'm seeing these damn tweens in my nightmares," one of them will tell me the next day, shaking his head like he's trying to dislodge an unpleasant memory. "I've worked Justin Bieber concerts. This is the same thing."
A colorful mash of backpacks, shorts, and Converse sneakers, the line is comprised mostly of groggy teenagers, who sit on the ground in circles, clutching water bottles, bags of Doritos, iPhones, and playing cards. Nothing about it seems nightmare-inducing.
That is, until a high-pitched scream slices through the quiet morning.
It spreads like a virus. "Oh my god, oh my god," girls suddenly chant in unison, their hands quivering by their faces in disbelief. Entering the building is a man in his thirties wearing a striped hoodie and jeans. I search for a teenage heartthrob, or a movie star, but the screaming is for him. He waves both of his hands and smiles before ducking inside.
Girls nearby soon inform me he is Hank Green, who along with his brother, John, founded VidCon five years ago. The screaming teenagers, who are here to attend the "world's premier gathering of people who make online video," recognize Green from vlogs the brothers post to their shared YouTube channel. And their success extends offline. Recently John's best-selling novel, The Fault In Our Stars, was turned into a movie that beat Tom Cruise's sci-fi thriller, Edge of Tomorrow, on opening weekend at the box office.
The rise of YouTube as a distribution channel is creating a new genre of fame that looks less like Tom Cruise than it does John and Hank Green–a shift that baffles just about everybody older than 18, including Hank Green. "I want to tell you a secret," he will explain later during a keynote speech. "I don't know what I'm doing. I have no idea. I don't think that any of us know what we're doing. There is a wave, and it's made of technological things and sociological things, and it's individual people making individual decisions about how they're going to spend their individual time. And we are riding it. And that's impressive. But it is not as impressive as understanding the wave."
Executives from entertainment companies, talent agencies, video startups, and, yes, YouTube itself, have come to VidCon with hopes of gaining that understanding. They have been let into the conference center early, and though none of them is old, per se, their accoutrements betray their age. Laptops, briefcases, coffee, and an occasional suit jacket separate them from the line outside far more than the wall of glass doors.
These "industry" badge-holders will spend the next several days on the third floor of the convention center–attending panels with titles like "Working With the Next Generation Of Talent" and listening to keynotes by industry leaders like DreamWorks Animation CEO 
Jeffrey Katzenberg–in an effort to decipher what is happening on the first floor. Most of them cannot reasonably blend in to a crowd of teenage girls. But I can. As the security guards visibly brace themselves for the doors to open, I tug on the straps of my baby blue backpack, adjust my ponytail, and prepare to enter the crazed world of YouTube fandom on the level where it lives.
A sea of girls is hoisting cell phones into the air. It's impossible to tell whether it's a line or whether there's something extremely interesting toward the center of the mob. A scream erupts from a far corner. "What's happening?" I ask a tall blonde girl next to me. "I don't know. Someone came out," she says.
I wander over to the next group and poke my head into their circle for clarification. "Hey, is this a line?" I ask. It is a line–a line to get into other lines that will lead to specific YouTubers' autograph signing booths once they open (the word is "YouTubers," by the way, not "YouTube celebrities" or "YouTube stars").
"Who are you here to see?" one girl asks. Nobody in particular, I tell her, you? "The British YouTubers."
Who? There are enough successful YouTubers that it would be impossible to know every star, and one person's hero can be, to another teenager, a total unknown. "You know, Jim Chapman, Alfie Deyes, Joe Sugg, Caspar Lee, Marcus Butler," the girl says. I don't know, and my blank expression is met with exasperated disbelief. It's time to move on.
As I bump around the crowd trying to figure out where the line starts, I learn that "Who are you here to see?" is the question at this conference in the way that "Where do you work?" might be the question at a professional networking event.
Some kids are here to see beauty vloggers like Michelle Phan (6.7 million subscribers), who posts tutorials about makeup and life advice on her channel. Another, typically older, crowd prefers the Jon Stewart-esque commentary of Philip DeFranco (3.3 million subscribers) and the news-based comedy channel he created called SourceFed (1.4 million subscribers). Others enjoy following daily updates from a family of six that goes by the name "Shaytards" (2.4 million subscribers). The Fine Brothers (9.3 million subscribers), who mostly direct rather than star in videos on their channel, attract an audience that is half comprised of people older than 25, though you'd never guess it here. Other corners of YouTube, like the extremely popular video game YouTubers, aren't even represented at VidCon, where teenage girls running after cute boy YouTubers are the most visible force.
A father-daughter pair have posted themselves strategically between the conference center and hotel, where they have decided there will be the greatest likelihood of spotting a star. Well, one star, in particular: Jenna Marbles (13.5 million subscribers), a 27-year-old with a colorful sense of fashion and a penchant for irreverent sarcasm.
The girl's father pulls his iPhone out of his pocket to show me a video of his daughter crying deliriously with happiness. "This is what happened when Jenna followed her on Twitter." He turns to his now embarrassed daughter, "show her the notebook."
His daughter rolls her eyes at him before she sheepishly pulls out a thick spiral notebook from her backpack. She has lined its pages with colored construction paper, on which she has pasted frames from each of Jenna Marbles' more than 200 videos. Written below each photo in marker is her favorite line from that video. "If we can find Jenna Marbles and give her the book, we win, and I can go home," her father tells me.
I soon discover that my own Jenna Marbles, the YouTuber who I would most like to hang out with, is 
Grace Helbig (1.8 million subscribers).
Grace–everyone here is on a first-name basis–has a deadpan, rambling humor that always seems to be apologizing for the previous joke. "Travel, it's good for your brain," she says in one video. "And also terrible," she pauses with uncertainty, "Travel is like this weird thing where it's so rewarding and so incredibly uncomfortable," another pause, eyes looking off screen like she's thinking, before she snaps back to the camera to announce definitively, "like sex!"
In January, she successfully ported her fanbase to an independent channel after parting ways with My Damn Channel, the content management company that hosted her daily vlog for five years. And in February, her star power helped sales of an Internet-only-realesed film she starred in, Camp Takota, keep pace with the Oscar-nominated movies in iTunes' independent film category.
She is 28 years old, just a little bit older than me. She studied improv at the same theater where I do. I feel like we're already friends, which, outside of VidCon, I would probably consider vaguely creepy on my part.
But the conference seems to be structured around this very feeling. Grace's schedule, along with all "special guest" YouTubers, is included in the VidCon app. She's hosting a "signing" for two hours on Saturday morning, and if I miss her there, she'll be at a Q&A session later in the afternoon. There's even a button I can use in the app to quickly add her appearances to my schedule.
I've picked a very popular YouTuber to hang out with.
When I arrive at the conference center at 8:00 a.m., one hour before the doors technically open and two hours before Grace's autograph signing begins, I use my press pass to skip the giant line outside and am shocked to find a packed conference floor. Five years ago, around 1,400 people came to VidCon. This year there are more than 18,000 attendees.
"Who are you here to see?" a woman in a blue polo shirt stops me as I head toward the line. I'm here to see Grace. "That line closed two hours ago," she tells me, adding that VidCon began letting some people in at 6:00 a.m. because the gathering outside had become a security hazard.
Fortunately for me, Grace has friends. Who, by extension, feel like my friends. She often appears together in videos with Hannah Hart (1.3 million subscribers), the originator of a delightful series called "My Drunk Kitchen" that is exactly what you think it is, and Mamrie Hart (570,000 subscribers), who created a series along a similar theme called "You Deserve a Drink." The three of them were co-stars of Camp Takota. Pods of YouTubers like Grace, Hannah, and Mamrie aren't uncommon. YouTubers form cliques just like high schoolers. They pop into each others' videos, comment on each others' channels, and, occasionally, date. Some of these groups formed long before any of its members were famous, and their members have helped each other by cross-pollinating audiences.
There's still space in Hannah's line.
It is here where I find my people. Emily Maddrey, the 15-year-old girl who stands in front of me with her mother, hasn't spent her time at VidCon running and screaming after British boys. She's been filming the girls who have been running and screaming as part of a documentary vlog she's making about the event. She thinks Hannah "is just so smart" and, in lieu of using the VidCon app, has written out her own schedule for the day, in ink. She likes my hiking sandals. And she's generously tolerant in educating me.
I learn that the bear hats in the next line are actually llama hats, a reference to Dan's "spirit animal" (that's Dan Howell, who describes his 3.8 million-subscriber channel, danisnotonfire, as "I let you laugh at my life so you can feel better about yours"). I learn that kids have painted cat whiskers on their faces not because Friskies sponsored face painting, but because Dan occasionally does a video with Phil Lester, the proprietor of the AmazingPhil channel (1.9 million subscribers), in which they both wear marker-drawn cat whiskers on their faces. I learn that Hannah has expressed enthusiasm for a carrot onesie, which is why she and Grace and Mamrie are dressed as carrots in the video playing on a nearby projection screen. I also learn that Grace, Hannah, and Mamrie are together known as the "holy trinity" of YouTube.
Emily approaches my YouTubers education with the familiar tone that my grandmother uses while catching me up on my cousins' lives. Charles Trippy (900,000 subscribers), a musician who documents his life on a daily show called "Internet Killed Television," had cancer. "He's getting better, but since chemo, he's had seizures." Some of them, she worries, could be nervous. "For the most part YouTubers are introverts, and when they come to places like this, it can be overwhelming. I know Zoella has had panic attacks before." She means 24-year-old Zoe Sugg (5.4 million subscribers), a cute British woman who recently sold two novels to Penguin, but most frequently posts videos about makeup, hair, and shopping.
Three hours later, it's our turn to meet Hannah.
I arrive at the first spot in line just as someone is throwing a banana to Hannah over a red tape barrier. She pulls me in for a hug. There's no need to convince me to like her–that's already been done as I have, for instance, watched her cook chocolate souffle while trashed ("ahhh, this is like where they talk about indirectly heating chocolate, and you're always like, blah, blah, blah. Fuck."). Before I really think about how bizarre it is, I'm talking to her like a friend who has by some weird twist of fate ended up, like a popular Disney character, as the attraction in front of this big line. "You must be exhausted," I tell her. Her face flickers with agreement before breaking back into an enthusiastic smile, "But I have a banana now."
It doesn't quite feel like meeting a celebrity. Celebrities are hair-sprayed and make-upped and otherworldly attractive. It's rude to approach them in New York and they hire people to hold back crowds around them. Hannah has put herself in front of a line that anyone is free to get into. We're excited to meet her, and she is just as excited to meet us.
"I've decided your fans are the best," I say, because I can think of nothing else to say, but also because it is true and also because I want her to like me. I believe her when she says, "I know! Aren't they the best?"
The cameraman "ahems" Hannah and me. We smile. I'm not sure what to do, so I throw one arm around her and another hand on my hip as the camera fires. There's one more shutter click, but I miss it. And there are no do-overs. So I pick up my backpack and head back through the long lines from which I came.
"Anybody who is not in line will not get a selfie," yells a guy wearing a gray T-shirt who turns out to be 25-year-old Sam Pepper (2.2 million subscribers), a YouTuber who frequently hits the streets of Los Angeles with pranks and personal questions (i.e., "How did you lose your virginity?").
Pepper has just been the impetus for yet another screaming mob of girls. By now, it's a familiar scene. One girl spots a famous YouTuber and then, almost as a courtesy to the other girls around her, screams. Hearing this high-pitched siren call, other girls nearby break into a sprint, asking each other as they dodge plants and benches, "who is it?" As wider and wider circles of girls spot the rush, they begin rushing, too.
But instead of muscling through with a security guard, Sam has stopped, braced each girl's back, and moved her into a long line of about 100 girls standing shoulder-to-shoulder. Each girl holds her phone out in front of herself and waits, in selfie stance, while Sam runs back to the beginning of the line and begins popping his face into the space between each pair of them, pausing long just long enough for each to snap a photo. "Sam, you're a genius," a girl yells as she walks by.
"Thank you!" he shouts back at her in between photos.
Two of his YouTuber friends, Harrison Webb (330,000 subscribers) and Mazzi Maz (640,000 subscribers), follow him, taking selfies along the same line. This is why fans pay at least $100 for a VidCon ticket. YouTubers want to meet you. They don't just shoot videos, they watch videos, too. Maybe they'll watch yours. And that's the sense that all YouTubers seem to wish to preserve.
It's what Hannah conveys when she tells fans at her Q&A that meeting them "is the moment I feel most alive." It's what Tyler Oakley (4.8 million subscribers) is saying when he orders pizzas for the fans standing in line waiting to meet him. And it's what iJustine (2 million subscribers) is proving when she assures an awkward 12-year-old boy that, yes, she would love to see a Snapchat of his skateboard.
When I Google "British YouTubers," I land on Alfie Deyes (2.7 million subscribers), who offers one explanation for why kids just hanging out in front of a video camera has proved so entertaining. "We are making our videos to please you, to make ourselves happy, and to just have a fun time," he says in a video titled "We Need To Have A Talk…." "That is literally it. I see comments online that are moaning, 'these young teens are nothing special.' That is why I think they are getting lots of views. Because these are just ordinary people who are able to brighten someon else's days. And the fact that they're not celebrities and not famous is what people like."
People who are ordinary, however, typically have no need to organize selfie lines. Increasingly, YouTubers are leading lives that look less and less like those of their fans.
That's in part because traditional entertainment companies are rushing to capitalize on their popularity. Disney recently acquired Maker Studios, a company that manages 55,000 YouTube channels, for $500 million. Nickelodeon and the Cartoon Network are giving YouTubers airtime. A television show based on the extreme cooking series Epic Meal Time premiered on A+E's FYI network in July. Makeup guru Michelle Phan has her own product line. And everyone has a book deal. Grace's book is called Grace's Guide: The Art of Pretending to Be a Grown-Up. Hannah's book is called My Drunk Kitchen: A Guide to Eating, Drinking, and Going With Your Gut. Mamrie's book is called You Deserve a Drink.
As more traditional entertainment companies get involved, it may be difficult to maintain the always kind, extremely approachable, and apparently uncensored atmosphere created by VidCon's founders. When I call Steve Honig, head of PR for VidCon, to ask him questions about the conference–like whether or not YouTubers get paid for showing up–he surprises me by launching into a 13-minute tirade in which he threatens to ban Fast Company from Vidcon in the future "if there's anything negative at all" in this article. "We have an arrangement," he insists (we do not). "And there better not be anything about 'no comment' in there, or Fast Company is not coming to VidCon next year." These tactics are not unusual in the traditional world of celebrity spin-doctoring–Honig used to represent Lindsay Lohan–but it's odd to encounter it in the context of YouTubers who are famous in part because they share their most personal thoughts with the world.
It's almost inevitable that the worship of authenticity, personal relationships, and equality between the fans and the famous, will take a hit at the expense of something much more profitable. Some draw parallels between YouTubers' nascent fame and the early days of ESPN or CNN, which, before they became profit powerhouses, seemed laughable in comparison to network channels.
"I believe to my core that the next generation of media businesses will look more like Michelle Phan and Phil DeFranco," says Bing Chen, YouTube's former creator development lead, who recently left to found a startup that builds apps for YouTubers' communities. "Michelle Phan is unequivocally this generation's Oprah Winfrey, FreddieW has, with RocketJump, become this generation's Steven Spielberg, Phil DeFranco and SourceFed has become this generation's Jon Stewart, if not Rupert Murdoch and News Corp."
I'm waiting at the main stage for Grace, Hannah, and Mamrie's segment. I've come from a joint Q&A session with all three of them, which seemed like a good place to meet them in person until I realized it would take place in the same giant hall where YouTube CEO Susan Wojcicki gave her keynote to industry badgeholders. Far more people showed up for the holy trinity. There was no hope of asking a question, and definitely no opportunity to start a conversation.
Now the trio enters to the '90s dance hit (recently resurrected in the animated film Madagascar), "I Like to Move It." Grace is wearing a cat onesie, Hannah is wearing a carrot onesie, and Mamrie explains that her onesie is at the dry cleaners. The three perform a skit in which they poke fun at marketing their books by dropping their preorder URLs into the dialogue (which of course, results in successful marketing for their books).
It makes me laugh, but it doesn't get me any closer to introducing myself. According to the VidCon app, this will be my last opportunity.
I have failed to meet Grace in person as a VidCon attendee. But as a journalist, I do get a 15-minute phone briefing with her and Mamrie. They're doing interviews to promote a new travel show they star in called #HeyUSA, which is launching on Astronauts Wanted, a joint venture between former MTV Networks CEO Judy McGrath and Sony Music.
"Everything we say is honest and personal, so of course, we've been having a two-way dialog for a long time," Grace tells me when I ask her and Mamrie about their relationship with their fans. "So come up and say hello, let's have a real in-person conversation, because I've told you a lot more about my life than I think my mother knows."
That's when the publicist jumps in to remind us to steer the conversation back to #HeyUSA.
Later, when I don't publish a news post about their new show, the PR person who set up our interview let's me know she'd prefer me to not quote Grace or Mamrie at all.
Like everything else at VidCon, there is a line to get in to prom, the closing event on the last day of the conference. Teenagers show up wearing sequins, floor-length dresses recycled from real prom, and the shorts and tank tops that they put on that morning. Many of them have asked their favorite YouTubers, via a tweet or a YouTube video, to be their dates. Tyler Oakley reverses the trend by asking who at VidCon would go to prom with him and gets more than 125 responses.
But Tyler is not at prom. Nor are most of the VidCon attendees who are legally old enough to vote.
At a nearby Sheridan, there's another long line. This one leads to an invite-only party hosted by content network Maker Studios. It has a casual outdoor patio ambiance, a DJ and, for guests older than 21, an open bar. A neon sign encourages attendees to "Dance to the beat of your own drum."
This is where Kian Lawley (610,000 subscribers), who I witnessed bring girls to tears by merely being spotted at VidCon, takes at least six turns posing with friends at a GIF photo booth. It's where Dan and Phil, who spent six hours posing for photos with fans earlier that day, end up, and where even Grace makes a brief early appearance.
"They were just hanging out, drinking and having fun," says Bridget Brown, a 19-year-old who recently signed up for Maker Studios' program for aspiring YouTube stars, about the famous YouTubers at the party. "And you were able to actually go up to them and network with them without it being overwhelming for them. You're not like, hey, I want your picture."
The kids at prom don't know about this other party. Standing against a backdrop of nearby Disneyland's nightly fireworks, wearing glow sticks like crowns, they emanate all the hope and adrenaline that powers interactions with the opposite sex when you're too young to drink. "VidCon Prom is where it's atttt!" tweets one of them. Girls inside take off their shoes. They link arms and skip across the dance floor, and co-ed circles form to hop up and down to the beat. All weekend, these kids have been chasing photos and autographs from their favorite YouTubers, but tonight they turn cameras on themselves, snapping selfies with new friends and taking videos to share with their own YouTube subscribers.
As I'm getting ready to leave, I'm interrupted by a scruffy blonde boy who, spotting my media badge, wants to know my name. He hands me a card for his YouTube channel (56 subscribers), on which he posts videos of himself blending things like doughnuts and tater tots into milkshakes. He dropped out of college. He doesn't travel much, except for this. As we talk, he keeps his arm wrapped around the shoulder of a girl who he met in this same spot yesterday.
"I'm a YouTuber, too," he says. "I'm just not as awesome as the famous ones." He thinks about it for a minute. "Well, I'm just as awesome," he corrects himself. "It's just I don't have as many views."