Ancient leaders gauged their popularity with applause. In Rome, the clapping of a crowd was coded in such a way—variations in volume and in speed and in style—that applause doubled as feedback for the people performing, be they artists or politicians. The crowd’s audible reaction to someone (“audience,” from the Latin for “hear,” derives from the sonic connection between those onstage and off) revealed that person’s standing with extreme efficiency. So applause—an early form of polling, an ancient realization of “big data”—was also a way for citizens to communicate with their leaders, political and otherwise. Reacting to something, loudly and intentionally, was a way for the populace to make their voices heard—such a common way, indeed, as to lead Cicero to remark, “The feelings of the Roman people are best shown in the theater.”

* * *

In early February of 2016, Beyoncé Knowles-Carter released “Formation,” her pop song and anthem and call-to-arms. The song and its accompanying video dropped, though really it is more accurate to say that they descended, on the Saturday before the Super Bowl, as people were weekend-ing and working and otherwise doing their typical Saturday stuff. Suddenly, though, the day and its respective banalities—its jobs and its errands and its birthday parties and its weddings and its Netflix binges—were transformed into an ad hoc high holiday. People around the country and around the world stopped what they had been doing to take in what Beyoncé had put out.

Beyoncé had, yet again, rippled the culture. And she’d done it in a way that was independent of, but of course also utterly reliant upon, her atomized audience. In response to “Formation,” people began doing pretty much the same thing those feisty Romans had done hundreds of years before: They gathered together, as an audience. They watched “Formation,” performatively. They reacted to it, publicly. They found new ways to applaud.

In the month since “Formation” came into the world, Zachary Campbell, ColorMePynk, Tierian La’Shae, and seemingly hundreds of thousands of others have shared videos of their reactions to the song and its video and the cultural moment it represents. Women, men, boys, girls, friends, couples, groups—some of them critical of the video, most of them awed by it—have taken to YouTube to dance and gawk and exclaim and, all in all, consider the ways that Beyoncé has, once again, slayed. They have done, basically, what any audience will, in the end: They have taken a thing out there in the world and—casually, insistently, joyfully—made it about them.

* * *

The reaction video may well be the quintessential genre of the nascent digital age. Enabled by YouTube and smartphones and iMovie and a cultural and political climate that both enforces social hierarchies and resents them, it carries its own internal aesthetics and motivations. It includes not just “Music Video Reaction Videos,” but also “Movie Trailer Reaction Videos” and “Sports Moment Reaction Videos” and “TV Scene Reaction Videos” and also—the deeper cuts, category-wise—“Scary Prank Reaction Videos” and “Kissing Prank Reaction Videos” and “Marriage Proposal Reaction Videos” and “Post-Anesthesia Videos” and (ready your Kleenex) “Cochlear Implant Activation Reaction Videos.”

The reaction video is related to “David After Dentist” and unboxing videos and those uber-popular streams that allow their viewers to watch other people play video games, but it is, in the end, distinct: The reaction video takes the Internet’s implicit recursiveness—its genetically determined tendency to feast upon itself—and renders it as culture. It takes the unpredictability of human emotion and turns it into literature. It is improv, played out at the scale of the Internet.

So: Here are some kids trying out old technologies. Here are some older people trying out new ones. Here are some sheltered people sampling “foreign” foods. Here are people taking things in. Here are people sending things out. Here is the Internet, introverted and extroverted at once. The reaction video, a user-generated and radically democratized outgrowth of Mystery Science Theater 3000 and I Love the ’90s and the mockumentary style of The Office, does the same thing those ancient Romans did, centuries ago: It protests against the invisible audience. It insists that the people will have their say. “I know most of y’all just probably want to see the video and don’t want to see me talking away,” Tierian La’Shae remarks before sharing her “Formation” reaction with more than 120,000 viewers. “But. I will give my two cents.”

* * *

The “Formation” reactions, as varied as they are, tend to share a formal similarity: a distinctly, insistently DIY quality that includes abrupt editing, volumes that soar and drop without warning or apology, and performances that refuse to acknowledge themselves as performances. Often, the speakers wear earbuds, bringing an eerily literal interpretation to “dancing to the beat of your own drum.” Sometimes the camera is shaky, evidence of an invisible videographer. Sometimes it is still.

ColorMyPynk’s “Formation” reaction is shot while she’s putting her makeup on to get ready for a Mardi Gras party. Guarnata Bourjolly’s reaction features her sitting on a chair, reading from notes she’s jotted on a legal pad; it is interrupted, mid-way through, by a camera malfunction. (“We just need to do some minor touches with this,” she tells her audience, adjusting the camera while it is still running.) ChrisMcCullyTv’s video begins with him declaring, “I literally just woke up … so we’re gonna get my natural reaction right now. I’m watching it.” (He goes on to remark, in the course of watching the video, “I’m scared!” and then, later, “My armpits are itching!”)

Uneak Tershai’s video features a clacking noise in the background—a noise that is unexplained until another person pops into the frame to announce, “Y’all, I’m typing a paper.” The friend watches the video for a moment, nods, says, “Yeah, I like that part,” and then returns to her paper, never to be seen again.

Some of the “Formation” reactions reinforce the hierarchical dynamics of celebrity. (ColorMePynk to a phantom Queen Bey: “You have slayed once again! You slay!” She will add, a bit later: “I need to go in the corner and pray … and think about my life and my existence.”) Many more of them, however, emphasize the flattening capabilities of digital media. Keyon Elkins’s “YOU’RE GAY” video—this one has nothing to do with Beyoncé; it is a reaction, instead, to people in his own life—constantly interrupts its speech with fourth-wall-breaking asides (“Oh my God, I look horrible”; “Sorry if it’s kind of echo-y in here, because I’m in my bathroom”).

Look at the tones of humility and empowerment twisting and twining in the “Formation” reactions. Look at how, on the one hand, the reactors genuflect—“I need to go in the corner and pray”—at the altar of Queen Bey. Look at how, on the other, their speeches are premised on the fact that they have appointed themselves as her critics. And look at how, as a result of that appointment, their reactions have gotten hundreds of thousands of views (from people, of course, reacting to the reactions). Uneak Tershai’s video, the one interrupted midway by an otherwise invisible paper-writer, has itself gotten more than 1 million views so far.

In that sense, reaction videos emphasize the mercurial divisions separating, at this moment in culture, action from reaction, creator from audience, thing from assessment-of-thing. They insist, in their casual entitlement—“I will give my two cents”—that “remix culture” is also, simply, “culture.” They are fit for a time that finds technology enabling cultural participation as never before; they are also fit for a public that carries out its conversations not just through books and magazines and TV shows, but also through memes and Facebook updates and Tumblr posts and live-tweeted TV shows and live-GIFed awards shows, through thinkpieces and hot takes and the recognition that, as A.O. Scott recently argued, “criticism is an art form unto itself.” Idiosyncrasy and universality, hierarchy and democracy, commercial culture and free, the death of the author and the ongoing life—there they all are, in 1s and 0s, rendering and streaming and dancing to Beyoncé.

And—it’s long been the case, but the “Formation” reactions make it especially clear—reaction videos emphasize the blurred lines between that which we think of as “politics” and that which we think of as “culture.” “Formation” is both a pop song and a multimedia speech about race and violence and Black Lives Matter. The videos reacting to it—which derive much of their drama from their tone of invited intrusion—acknowledge, overtly and less so, its political dimensions. If Beyoncé’s song is a call to arms, then the thousands of videos reacting to it are her troops, coming forward and revealing themselves.

* * *

The reaction video as a genre was born, by most accounts, in early 2006, when the YouTuber raw64life uploaded a video—recorded in 1998—of a kid and his sister on Christmas Day. The kids unwrapped, this being ’98, a Nintendo 64. And they proceeded to freak out, adorably. Their video—“Nintendo Sixty-FOOOOOOOOOOUR,” it’s called—went viral. Today, it has more than 20 million views and more than 48,000 comments.

A seeming formula for virality having been found, similar videos followed. And then … came “2 Girls 1 Cup.” The shock video—a trailer for the pornographic scat-fetish film Hungry Bitches, which is really all that needs to be said about that—became instantly (in)famous. And, almost immediately, reaction videos stepped in to fill the vacuum left by the flight of human decency: Instead of watching the shock video, people could watch other people watching it. “2 Girls 1 Cup,” the critic Sam Anderson noted, “generated a whole menu of human response: You could watch a grandmother watching it or a room full of Marines or a group of nursing students or the porn star Ron Jeremy or the ultimate fighting champion Rampage Jackson or—on the show Tosh.0an entire studio audience. Soon it matured into a full-blown Internet meme, which means you could also watch the reactions of Super Mario, Darth Vader, Kermit the Frog, Stewie from Family Guy, and multiple cats.”

The reaction video was thus, via a combination of people wanting to be shocked and fearing it, newly recognizable as a genre. In late 2008, “reaction video” made its way onto Urban Dictionary (according to one Señor Giggles, a reaction video is “a recording of a reaction to a disturbing or frightening image or video”). In 2011, the genre got a spirited write-up in The New York Times (under the revealing headline “Reaction Videos as Anthropological Study of America”). Soon people were rushing to post reactions to Game of Thrones’s Red Wedding. And to the new Star Wars trailer. And to basically anything that was getting traction online. (Witness the bit of cultural anthropology that is “Funniest Reaction to ‘Scarlet Takes a Tumble’ Video.”) The reaction video became sort of ubiquitous. To the extent that any time a major cultural product—a Rihanna song, a Kanye album—comes out, videos reacting to it are de-facto extensions of that product.

There’s good reason for that. The reaction video may be about people watching people watching people; it is also, however, about the pleasures of watching as a group. As an audience. As a fandom. As a public. Reaction videos are popular for the same basic reason that 20 million people tuned in to watch the live simulcast of Kanye’s Yeezy Season 3: We’re social animals. We know that, in a profound way as well as the glib one, sharing is caring. Reaction videos allow us to take a thing and make it our thing.

As Kate Miltner, a scholar of Internet culture at the University of Southern California, told me in an email,

I know that when I share a video I love with someone I watch their faces (if we are in the same place or on video chat) more than I watch the video itself because I want them to love what I have sent them just as much as I do, and I *really* want them to specifically love those key moments—because if they do, then it’s a thing we can continually reference. It moves from media text to shared experience to personal reference/joke. Sharing media is about creating connection, and when we see total strangers react just like we did to a media text we love, there’s something really gratifying about that—it makes us feel part of something bigger while at the same time validating our own personal tastes and experiences. Toss a funny reaction or a cute kid in there and you’ve got YouTube gold.

Which is not to say that reaction videos are purely earnest, or purely DIY, or purely artistic in their impulse. Some of their success, YouTube-views-wise, must be attributed to people searching for the original video and mistakenly arriving at a reaction. (As one commenter noted in response to one of the “Formation” reactions: “hate when you’re thinking you GONNA watch the video and these things want to DAMN have a talk show.”)

And the videos can also, being produced both by and for the Internet, be ironically self-referential. The Fine Brothers—the creators of the immensely popular Teens React series on YouTube—also produce a show called, more generally, YouTubers React. One of its episodes, posted last year, is titled “YouTubers React to Every YouTube Video Ever.” And one of the show’s reactors, Tyler Oakley, recently uploaded his own video. Its title? “Tyler Oakley Reacts to Teens React to Tyler Oakley.”

The legal scholar Tim Wu calls it “The Cycle”: the inevitable organic-to-institutionalized trajectory that most any media property will take as it moves from “disruptive” to “ubiquitous.” And, indeed, the reaction video, in short order, was co-opted by brands both corporate and personal. Buzzfeed adopted the premise of the reaction video for its “People Try X for the First Time” conceit. The creator of “HOW COULD YOU DO THIS KRISTEN?!” followed that video up with many more—significantly less trafficked—rants: repeated attempts, it seems, to make lightning strike again. Celebrities began to use the videos as personal brand extensions. (Thus, YouTube video titles like “Celebs React to the Red Wedding.” And headlines like “Arya Stark Posts Reaction Vine to Game of Thrones Red Wedding.”)

Celebrities also, of course, joined the chorus reacting, publicly, to “Formation.” John Legend. Uzo Aduba. Mindy Kaling. Sophia Bush. Raven-Symoné. Rudy Giuliani. Pop Sugar offered “9 Celebrity Reactions That Perfectly Describe How You Felt When Beyoncé Dropped ‘Formation.’” Southwest Airlines got in on the (re)action. So did, because of course, Red Lobster.

There’s a kind of inevitability to all this. As Clay Shirky, the author of Here Comes Everybody: The Power of Organizing Without Organizations and Cognitive Surplus: Creativity and Generosity in a Connected Age, told me in an email, “What YouTube showed us is that people your age and especially mine have no idea what makes for compelling viewing, because prior to now, no one has ever tried any sort of experimentation.” The reaction video is one way of engaging in this experimentation—a genre, essentially, that has arisen from the primordial YouTube and proved its Darwinian mettle. And its environmental fitness is unsurprising. “If people like domino vids, and they like Fail vids,” Shirky says, “then ‘The Ultimate Fail Compilation (Domino Edition)’ seems like something of an obvious move, no? And if domino fail compilation videos are obvious, then how much more obvious is collating the pleasure of watching someone else have surprising experiences?”

* * *

“Reaction,” as a term, suggests a kind of scientific automation: the action, the equal and opposite reaction. And while, as Shirky suggested, there is a kind of anthropological obviousness to the reaction video, what is perhaps most striking about the genre is how deeply unpredictable its individual videos have proven to be. Did you expect that watching a pop video would lead one woman to prayer? Probably not.

In that sense, the reaction video is a commercial phenomenon as well as a cultural one. It used to be that audiences—who are also, so often, consumers—“reacted” to something with the stark bilateralism of the commercial transaction: by buying the ticket or not, by buying the book or not. They belonged to a system in which audiences doubled as a collection of disembodied dollars: Creators created; consumers either yayed or nayed in response; the creators learned from the yay-nay dynamic; the circle moved on. It’s a cycle that is changing, slowly, but that has deeply infiltrated our mode of thinking when it comes to judging the value of artistic production: Even today, critics (and, in particular, “reviewers”) tend to make the mistake of conflating commercial success—“box office,” as a hazy yet very specific metric—and artistic.

The reaction video is, on top of so much else, a rebuke of the decision-via-dollar dynamic. It cares very little about “box office” or Nielsen numbers or what have you; it cares instead about art’s ability to bring people together in ad-hoc communities and fandoms. The videos may not be the stuff of high criticism—there is very little, in general, to be found of historical context or literary comparison or anything else that might otherwise be encountered in the New York Review of Books—but they do something that is just as valuable in the age of the quantified audience: They take an artistic product on its own terms. They reinforce the notion of art for art’s sake.

And: They do the same thing those ancient Romans did, when they cheered and booed and clapped for their leaders: They insist that “the audience,” in a culture of Yelp ratings and Uber stars and YouTube views, is not just a mess and a mass of demographics, but also a collection of humans. They transfer that audience from passive consumers of culture into active creators of it. And they celebrate the ability good art—high or pop or in-between—has of inspiring you and collecting you and making you say, as ColorMePynk did when she saw “Formation” for the first time: “I need to go in the corner and pray.”