‘‘The numbers are amazing,’’ Huffington said as staff members filed out. ‘‘You’re not as likely to share a story of a beheading. Right? I mean, you’ll read it.’’  Within The Huffington Post, and away from the glass table, some staff members have fretted that What’s Working could result in a steady drip of pallid, upbeat stories (e.g., ‘‘How Hugh Jackman’s Coffee Brand Is Changing Lives’’). But it’s hard to argue with Huffington’s intuitions when it comes to generating traffic. Her site has more than 200 million unique visitors each month, according to comScore, and it is one of the country’s top online destinations for news.  Nevertheless, in May, Huffington’s tenure as editor in chief was briefly in question. The site’s corporate parent, AOL, was sold to Verizon for $4.4 billion, and Huffington was forced to spend a few weeks negotiating the terms of the site’s future with her new overlords. During that process, AOL revealed that two suitors, earlier in the year, tried to buy The Huffington Post for $1 billion, or roughly four times what Jeff Bezos paid for The Washington Post two years ago. Plainly, to certain investors, digital media companies are valuable because they deliver enormous audiences. Any difficulty turning a profit — The Huffington Post broke even last year on $146 million in revenue, according to someone familiar with the site’s finances — is considered a temporary problem that will eventually be fixed by the sheer size of the readership.  This singular focus on audience development expresses itself in different ways at different publications. At The Huffington Post, it takes the shape of an editorial mandate that, much like the universe itself, is unfathomably broad and constantly expanding. At least in theory, nothing gets past its editors and writers. They cover, in most cases through aggregation, everything from Federal Reserve policy to celebrity antics, from Islamic State atrocities to parenting tips, supplemented with a steady stream of uncategorizable click bait (‘‘Can Cannibalism Fight Brain Disease? Only Sort Of’’).  To work at The Huffington Post is to run a race without a finish line, at a clip that is forever quickening. The pace is stressful for many employees, who describe a newsroom with plenty of turnover. One former staff member I spoke with, who developed an ulcer while working there, called The Huffington Post ‘‘a jury-rigged, discombobulated chaos machine.’’  Huffington may be the Internet’s most improbable media pioneer. This is her first job as an editor or publisher, and few would describe her as a techie. But as one of the first major media properties born in the full light of the digital age, The Huffington Post has always been a skunk works for the sorts of experiments that have come to define the news business in the Internet era.  In its early days, when most visits came through Google searches, the site mastered search-engine optimization (S.E.O.), the art of writing stories based on topics trending on Google and larding headlines with keywords. The site’s annual ‘‘What Time Is the Super Bowl?’’ post has become such a famous example of S.E.O.-driven non-news that other media outlets have written half-disgusted, half-admiring posts dissecting its history.  When most sites were merely guessing about what would resonate with readers, The Huffington Post brought a radical data-driven methodology to its home page, automatically moving popular stories to more prominent spaces and A-B testing its headlines. The site’s editorial director, Danny Shea, demonstrated to me how this works a few months ago, opening an online dashboard and pulling up an article about General Motors. One headline was ‘‘How GM Silenced a Whistleblower.’’ Another read ‘‘How GM Bullied a Whistleblower.’’ The site had automatically shown different headlines to different readers and found that ‘‘Silence’’ was outperforming ‘‘Bully.’’ So ‘‘Silence’’ it would be. It’s this sort of obsessive data analysis that has helped web-headline writing become so viscerally effective.  Above all, from its founding in an era dominated by ‘‘web magazines’’ like Slate, The Huffington Post has demonstrated the value of quantity. Early in its history, the site increased its breadth on the cheap by hiring young writers to quickly summarize stories that had been reported by other publications, marking the birth of industrial aggregation.  Today, The Huffington Post employs an armada of young editors, writers and video producers: 850 in all, many toiling at an exhausting pace. It publishes 13 editions across the globe, including sites in India, Germany and Brazil. Its properties collectively push out about 1,900 posts per day. In 2013, Digiday estimated that BuzzFeed, by contrast, was putting out 373 posts per day, The Times 350 per day and Slate 60 per day. (At the time, The Huffington Post was publishing 1,200 posts per day.) Four more editions are in the works — The Huffington Post China among them — and a franchising model will soon take the brand to small and midsize markets, according to an internal memo Huffington sent in late May.  Throughout its history, the site’s scale has also depended on free labor. One of Huffington’s most important insights early on was that if you provide bloggers with a big enough stage, you don’t have to pay them. This audience-for-content trade has been imitated successfully by outlets like Thought Catalog and Bleacher Report, a sports-news website that Turner Broadcasting bought in 2012 for somewhere between $150 million and $200 million.  As this more-is-better ethos has come to define the industry, shifts in online advertising have begun to favor publications that already attract large audiences. Display advertising — wherein advertisers pay each time an ad is shown to a reader — still dominates the market. But native advertising, designed to match the look and feel of the editorial content it runs alongside, has been on the rise for years. BuzzFeed, the media company started in 2006 by Jonah Peretti, a co-founder of The Huffington Post, was built to rely entirely on native advertising. The Huffington Post offers to make its advertisers custom quizzes, listicles, slide shows, videos, infographics, feature articles and blog posts. Prices start at $130,000 for three pieces of content. This is where size matters; top-tier sites can fetch premium rates because advertisers know their messages could be seen by millions. There have been concerns that readers might be deceived by native ads if they are not properly identified — The Huffington Post always clearly labels its sponsored content — but the ethical debate in the media world is over. Socintel360, a research firm, predicts that spending on native advertising in the United States will more than double in the next four years to $18.4 billion.  Kenneth Lerer, another Huffington Post co-founder, believes that news start-ups today are like cable-television networks in the early ’80s: small, pioneering companies that will be handsomely rewarded for figuring out how to monetize your attention through a new medium. If this is so, the size of The Huffington Post’s audience could one day justify that $1 billion valuation. But at least in cable, the ratings-driven mania of sweeps week comes only four times a year.  Even as she oversees an international news operation, Huffington spends most of her days and nights in a globe-spanning run of lectures, parties, talk shows, conferences and meetings, a never-ending tour that she chronicles in a dizzying Instagram feed. Her stamina is a source of awe to members of what she calls her A-Team — the A is for Arianna — a group of 9 or so Huffington Post staff members who, in addition to their editorial duties, help keep her in perpetual motion. Within the organization, A-Team jobs are known to be all-consuming — but also, for those who last, a ticket to promotion later on. While some stick around for years, many A-Teamers endure only about 12 months before calling it quits or asking to be transferred.  The first time I saw Huffington’s unremitting style up close was in New Haven last year, at the start of a tour to promote her self-help book, ‘‘Thrive.’’ In all of our interviews, she was warm and entertaining. She has a politician’s gift for seeming sincerely interested, having learned that nothing is so disarming as asking personal questions and then listening. She also has a comic’s timing. At a Barnes & Noble onstage chat in Manhattan, shortly before the trip to New Haven, the moderator, Katie Couric, asked her who was to blame for the merciless pace of life in corporate America. Huffington paused for a moment. Then she turned to the audience.  In her talk, she described her own transformation from fast-lane addict to evangelist for reflection, sleep and ‘‘digital detoxing’’ — basically, turning off your smartphone whenever possible. This is a catechism she has branded the ‘‘third metric’’ of success, with money and power being the first two. Her conversion narrative begins on the morning of April 6, 2007, when she collapsed from exhaustion. She fell to the floor in her home office, hitting her face on her desk and breaking her cheekbone. Medical tests found nothing that could explain the episode. Huffington realized that her lifestyle, which at the time was filled with 18-hour workdays, seven days a week, was wrecking her health.  ‘‘By any sane definition of success,’’ she told the crowd that day in New Haven, ‘‘if you are lying in your office in a pool of blood, you are not a success.’’  The speech, which I caught a few times, is always a hit. Huffington presents herself as a redemption story, someone who overdosed on her mobile phone and survived to warn others. She looks the part, too: a Dolce & Gabbana-ed woman of a certain age, perfectly at ease, regularly brushing back a forelock of honey-blond hair with her fingers. After the speech in New Haven, people lined up to have their copies of ‘‘Thrive’’ signed. One by one, they offered Huffington variations of, ‘‘You are an inspiration.’’ Some shared their own success stories.  One woman told her: ‘‘In the horse world, I do holistic care, and I’m embarking on a barn that’s cutting-edge. It’s all about positive reinforcement.’’  ‘‘We’d love you to write about it!’’ Huffington exclaimed.  Five years ago, in 2010, the site was successful, attracting nearly 25 million unique visitors a month, but it lacked the money Huffington felt it needed to expand. So it seemed fortunate when, later that year, she met Tim Armstrong, chief executive of AOL, at a media conference in New York.  ‘‘He asked to meet with me privately, and he said: ‘What do you want to do with The Huffington Post?’ ’’ Huffington recalled. ‘‘And I said, ‘I want to be a global company, I want us to be everywhere in the world.’ ’’  Armstrong offered $315 million, and on Feb. 7, 2011, AOL announced the acquisition. Huffington was made the head of the Huffington Post Media Group, an entity that would control AOL’s empire of content — an odd mixture of offerings including Moviefone, TechCrunch, Engadget, MapQuest, Autoblog, AOL Music and the collection of hundreds of hyperlocal websites called Patch. In a stroke, Huffington found herself overseeing a diverse portfolio with 117 million unique visitors per month in the United States and 270 million around the world. She also managed several thousand editors, writers, bloggers and business staff members.  Initially, Armstrong and Huffington seemed like a natural match. Each is a fan of big ideas that can be executed quickly; each prizes boldness and energy. At one AOL meeting with brand managers, Armstrong ribbed his underlings by recounting how Huffington called him on a Sunday to tell him what was wrong with AOL’s home page. Why had no one else done that?  Integrating a group of such varied websites and personnel would have posed a challenge to any manager. For one who admits to having little interest in organization and planning, it was impossible. Huffington preferred to improvise, and she did so aggressively — ‘‘like a hockey player,’’ as one former AOL executive put it, with some admiration.  A clash of cultures, however, was soon evident. Many of AOL’s sites did little more than promote their sponsors; AOL Real Estate, for instance, was mainly a home for Bank of America ads, next to stories about the joys of mortgage refinancing. In an attempt to restore some semblance of editorial integrity, Huffington fired the freelancers who worked for the site and replaced them with young staff members. Many were recent graduates of Yale — her feeder of choice — whose chief qualification, aside from the obvious, was a willingness to work for a pittance. But the hiring spree was rushed and filled the sites with fledglings. Page views plunged, irking corporate sponsors.  At first, many on Armstrong’s team had been awed by her energy and range, but they quickly grasped that these didn’t always translate into results. ‘‘No one else could give a commencement speech at Smith one day, meet the prime minister of Japan on Tuesday and debate the Middle East on MSNBC on Wednesday,’’ one former executive said. ‘‘But that doesn’t mean she knows the ins and outs of running Moviefone.’’ It didn’t help that AOL stock, following the acquisition, had fallen to less than $12 by August from just above $20 at the time of the purchase half a year earlier. At some point, Huffington stopped going to meetings of AOL executives, and in April 2012, an organizational reshuffling quietly moved every AOL site except The Huffington Post out of Huffington’s portfolio. Her tenure as AOL content czar was over.  By then, Huffington was having a serious case of seller’s remorse. During a tech conference, she was overheard at a bar in Rancho Palos Verdes, Calif., talking to the venture capitalist Scott Stanford, then a Goldman Sachs banker. Speaking in a voice loud enough for many to hear, she posed questions like, ‘‘Who would buy The Huffington Post?’’ and ‘‘How much would it fetch?’’ Around that time, Huffington Post employees recall, she went on trips with very rich people and returned with news that the site was about to be purchased again, this time for $1 billion.  But The Huffington Post was no longer Huffington’s to sell, and AOL seemed uninterested in parting with it. By October 2012, discontent with Huffington was widespread enough that top executives at AOL were quietly strategizing about ways to ease her into a kind of ceremonial role — one in which she would only promote the site rather than running its day-to-day operations. (A source said the effort was given a one-word shorthand: ‘‘Popemobile.’’ Like the Pope in his bulletproof bubble, Huffington would glide through the world and wave.) The idea never caught on, mostly because it was clear Huffington would never agree to it, and by May of this year, when Verizon announced its acquisition of AOL, it had long been abandoned.  Verizon went after AOL principally for its ad-buying technologies, but in mid-June, Verizon’s C.E.O. and chairman, Lowell McAdam, said he was committed to keeping The Huffington Post, as incidental as its acquisition may have been. Huffington, whose contract with AOL expired earlier in the year, wanted guarantees that Verizon would finance the site’s growth and keep its hands off articles with which it may have a difference of opinion — those on net neutrality, for instance.  Soon after the Verizon-AOL deal was announced, Huffington began to negotiate her future and the future of The Huffington Post. According to two sources, Armstrong suggested closing the acquisition first and prodding Verizon to make promises about The Huffington Post later. Huffington refused, and she held out until mid-June, when Verizon pledged more than $100 million a year for ongoing operations and vowed to give the site editorial autonomy. (Others with knowledge of the talks say that no financial commitments have been made yet.) The money will allow The Huffington Post to broaden its video offerings, supporting a 24-hour online network and what Huffington called, in an internal memo, a ‘‘rapid-response satire unit.’’ Assurances in hand, Huffington signed a new four-year contract that will keep her in situ as editor in chief.  None of this necessarily means that The Huffington Post will remain in Verizon’s permanent portfolio. In fact, if Verizon’s real goal is to offload the site, it has done exactly what it should to burnish the asset for eventual sale. Were suitors to come courting again, they would surely offer less for a Huffington-less Huffington Post.  That is not to say that Huffington is inexpensive to keep around. She flies all around the planet, occasionally with members of the A-Team in tow. A-Team duties include tending to Huffington’s Twitter account, her Instagram feed and her Facebook posts; running her errands; organizing her day; planning her travel; and prepping her speeches, which, if they aren’t pro bono, cost at least $100,000. One former A-Teamer recalled loading The Huffington Post on Huffington’s computer when she showed up at the office.  ‘‘Arianna doesn’t surf the web,’’ the former A-Teamer explained. ‘‘She reads stories that people send on her iPhone, and she sends and receives emails on her BlackBerry. But I’ve never seen her on a computer, surfing the web.’’ Huffington said that this is not true, and stated that she ditched her BlackBerry nearly two years ago. But more than a dozen former and current Huffington Post staff members said they had never seen her so much as open a web browser.  Some former employees file this in the category, Things at Odds With Arianna’s Public Image. Also in this category is the vibe at The Huffington Post’s downtown Manhattan office. Despite its nap rooms, meditation rooms and breathing classes, which were introduced as Huffington entered her ‘‘Thrive’’ phase, it is described as a surpassingly difficult place to work.  Much of this difficulty is inherent to life at an Internet news site, where victory means beating the competition by a matter of seconds with a post that might yield gobs of traffic. This is why so many editors and writers at The Huffington Post remain at their desks during lunch and keep an eye on the web at all times. If, while you’re offline, three new Instagram filters are announced and you’re late to post the news, that’s a problem. ‘‘Just about everyone works continuously, whether you’re at the office or not,’’ one former employee said. ‘‘That little green light that says you’re available on Gchat is what matters.’’  Low pay worsens the strain. One former employee said that some staff members take second jobs to cover their expenses. Some tutor; others wait on tables; others babysit. (A representative for The Huffington Post said the company was unaware of any moonlighting.) Many staff members rely on what has been called ‘‘HuffPost lunch’’ — Luna Bars, carrots, hummus, apples, bananas and sometimes string cheese, all served gratis in a kitchen area of the office.  Inevitably, there is burnout. At the New York office, nearly two dozen employees have left since the start of this year, either because they were laid off or found more enticing and less hectic jobs. A Gawker post in early June, written by an anonymous former staff member, said the recent departures were hardly a surprise because the place has long been ‘‘so brutal and toxic it would meet with approval from committed sociopaths.’’  A former editor told me about a period in 2013 when a series of departures left a cluster of empty desks along a wall that Huffington walks past on the way to her office. ‘‘Someone told my manager, ‘Arianna is really stressed out about the number of people leaving, so we need a bunch of people to sit at those desks in the path from the elevator to her office, to make her feel better,’ ’’ the former editor said. ‘‘So we sat there, waiting to say: ‘Hello! Greetings!’ as she walked by. It was supposed to be for two hours, but she got there at about 3 in the afternoon instead of 11 in the morning. It was absurd. I had to interrupt my workday because this woman was stressed out, because so many people had left, because they were stressed out.’’ (A Huffington Post representative denied this story, saying it was ‘‘clearly made up by someone with an ax to grind.’’)  Staff members in Huffington’s inner circle must also contend with her superhuman endurance. Her oft-repeated claim to sleep eight hours a night notwithstanding, she rarely seems to be idle. Emails from her cease, several ex-employees told me, only between 1 a.m. and 5 a.m.  There are staff members who have stuck it out for years and speak highly of the site as a place to work. They say they form lasting bonds with co-workers and relish the sense that they are writing for millions of readers. Some, like Daniel Koh, a former A-Teamer, speak with a reverence and fondness for Huffington herself. Koh described her as a perfectionist of exceptional intellectual wattage, a leader who never raises her voice and never holds a grudge. ‘‘Was it intense, and long hours, and did she teach me to maximize my workday?’’ he said. ‘‘Absolutely.’’  But others who have worked closely with Huffington have found it a bruising experience, saying that she is perpetually on the lookout for signs of disloyalty, to a degree that bespeaks paranoia or, at the very least, pettiness. Employees cycle in and out of her favor, hailed as the site’s savior one moment, ignored the next. (The Gawker post called the office ‘‘essentially Soviet in its functioning.’’) ‘‘Everyone’s stock is shooting up or falling at any given moment, so everyone is rattled with uncertainty and insecurity,’’ one former employee said. ‘‘I’ve never seen anything like it.’’  When I asked Huffington about criticisms of the newsroom, she was unmoved. She pointed to the nap rooms and breathing classes as evidence that she took employee well-being seriously. Only the voices of current employees were worth listening to, she cautioned, because the opinions of people who were laid off or left were likely to skew negative. I noted that she seemed unwilling to accept any responsibility for what a lot of former employees said was a vexing atmosphere.  ‘‘I’m definitely a work in progress,’’ she acknowledged. ‘‘I’m not by any means saying I’m perfect. But I feel very good about our culture here, because a lot of our top leaders have embraced it.’’  The Huffington Post is hardly the only web media company with a reputation as an arduous place to work. Nor is Huffington the only editor in chief considered capricious and exasperating by employees. But she is surely the first described in those terms to install hammocks in a newsroom. Only someone with her unique combination of drive and outward placidity could run a tremendously popular, hugely productive website and then begin a second career chastening us for our addiction to the Internet. Somehow she has pulled it off. In her site’s parenting section, some of the most successful posts target moms who are checking their Facebook feeds late at night, apparently yearning to be told that they shouldn’t be on Facebook at that hour. ‘‘You know, posts about, ‘Stop procrastinating and go sleep,’ ‘Disconnect your devices,’ ’’ said Ethan Fedida, the site’s senior social media editor. ‘‘They go crazy for it.’’  It’s as though Huffington is spreading an illness while simultaneously peddling the cure. Call it hypocrisy, but it testifies to her savvy. The business of web media is figuring out what people want — and if what we want is contradictory, why shouldn’t Huffington profit from that contradiction?  Huffington may be engaged in a bit of wishful projection when she presents herself as an apostle of serenity. But it is a veneer she never drops, at least in public. At the Barnes & Noble event for ‘‘Thrive’’ last year, the one moderated by Katie Couric, a young woman rose during the question-and-answer session.  ‘‘What do you say to employers who are now seeking people specifically to work in social media?’’ she asked. ‘‘Our job is to be connected 24-7, where we have to manage your Facebook, your Instagram, your Twitter, your Pinterest. How do we detox when we’re told we have to be in the social-media revolution in order to earn our living?’’  After thinking for a moment, Huffington suggested that she tell her employer that tweets can be scheduled in advance, so she doesn’t have to be awake at all hours. Remind your boss that people are paid for their judgment, Huffington added, not their endurance. Couric then asked the young woman, ‘‘You think your boss would be receptive to that?’’  All eyes turned back to Huffington. Some bosses are toxic, she offered, so start looking for a new job. With a smile, she added: ‘‘We’re hiring.’’  David Segal is a business reporter for The Times.  Sign up for our newsletter to get the best of The New York Times Magazine delivered to your inbox every week.  A version of this article appears in print on July 5, 2015, on page MM28 of the Sunday Magazine with the headline: Her Domain . Today's Paper|Subscribe
She did more than anyone else to invent the Internet news business. After a decade, despite setbacks, she is still setting the pace.