Documentary. A starchy word, isn’t it? It comes from the Latin documentum, meaning lesson or proof, and carries an implicit threat: “Time for class, children.” That’s better than a quiz, for sure, but nothing you’d want to pay thirteen bucks to see on a big screen. A popular website for doc practitioners is called “the D-Word,” as in (creator Doug Block explains), “We love your film but don’t know how to sell it. It’s a D-word.”

A good place to learn to love the D-word is a film festival like Tribeca (April 17 to 28), where you have the opportunity to marvel at the explosion—and creative flowering—of this most commercially unsexy of genres. I was down in Miami for an excellent fest last month and out of my mind with pleasure at the opening movie, a doc called Twenty Feet From Stardom that centers on great backup singers trying to make their own voices heard (you’ll hear about it, boy will you, when it opens in June); when the lights came up, doc programmer Thom Powers (lucky bastard) announced, “Ladies and gentleman, Darlene Love,” and one of the stars of the film walked out, and the audience rose to its feet screaming as Darlene let loose in song. I wish you’d been there to feel the, well, love.

This week, I want to be at Tribeca for the opening feature about the beloved group the National (the band will do a show), and to pay my respects to the ­whistle-blowing (and persecuted) protagonist of the stunning The Kill Team, in which a psychotic platoon sergeant ­choreographs killings of Afghan civilians for kicks (he plants weapons on them to make it seem as if the soldiers were attacked), as well as the lone heroic cop of the superb archival-footage doc Let the Fire Burn, about the 1985 bombing of the radical African-American Move organization in Philadelphia. I want to see these films in a public place with their subjects in attendance before an all-­embracing crowd.

More than that, I want to sell you hard on the notion that in this age of digital video—in which there are cheap cameras, editing software, and funding to be had (if rarely big money to be earned)—the cool kids are making docs. The form is not just good for you these days. It’s incredibly sexy.

Geoffrey Gilmore, chief creative officer of Tribeca Enterprises, bridles at how neglected the D-word is in the larger scheme. There hasn’t been any good, serious writing on the subject in decades, he says, so we’re stuck with the stereotype of solemn PBS programs with “a frame of politics and social issues” rather than more entertaining “character-driven” or narrative works. (Here I must add that PBS’s Frontline and POV docs are generally brilliant and—though they preach to the choir—essential.) On a panel with me a few years ago at the Silverdocs fest in Silver Spring, Maryland, Powers wished aloud for full-time mainstream doc critics who’d cover more and know what the hell they were talking about. I hung my head.

But how can you cover it all? There are now so many directors and production entities that for every person I’ve talked to for this article there will be a thousand saying, “Why didn’t he talk to me?” They want to be acknowledged, profiled, and have their work reach larger audiences.

Why so many docs? For one thing, there are more outlets for exhibition—not just via commercial releases but in festivals, on cable, via video on demand, and over the Internet. There is funding: HBO looms large thanks to a unit overseen by Sheila Nevins. There’s PBS, ESPN, ­Sundance, Tribeca. The Ford Foundation is giving out $50 million. There are outfits like Impact Partners, run by Dan Cogan (husband of acclaimed doc director Liz Garbus), which has a waiting list of investors wanting to put money into socially conscious docs. Scores of applications (and rough cuts) pour into the above offices weekly. Probably more people want to make docs than regularly go to see them in theaters.

But you don’t need much money to begin. “There’s a whole generation of people who just literally pick up a camera to make films and they don’t start off thinking, I’m going to make a documentary,” says Robert Greene, who made a wonderful amateur-wrestling doc called Fake It So Real. “It’s more like, ‘I have my friends, I have my issues. Let’s make a film with my friends and my issues.’ ”

We have the means to document everything—ourselves, our cats, our bad weather, our subway flashers, our friends, our friends being beaten by cops … Thirty years ago, you might have owned a Super 8 camera, but the films had no sound and cost money to develop. Home video cameras changed that, but the image was lousy back then and you still needed expensive equipment to edit your footage. Then came software, and you were closer than ever to making “real” films. But it wasn’t until the advent of small digital cameras that the line between video and celluloid began to blur. And in the past few years there has been a leap in technology. A few thousand dollars for a first-rate camera and editing software, and you’re good to go.

Everyone I talked to emphasized that documentary doesn’t mean one kind of film anymore. There are so many over­lapping subgenres. Among them:

1. Vérité. “Fly on the Wall.” Think Frederick Wiseman and his landmark sixties and seventies films. The camera runs on and on, but the filmmaker still shapes our perceptions. The Maysles films (Salesman, Grey Gardens) were more shaped and even more influential. There’s not much rigorous vérité these days, because the audience won’t sit still. Albert Brooks made the definitive vérité parody, Real Life, in which a megalomaniac filmmaker burns down the house of the family he’s covering.

2. Investigative journalism. The most familiar subgenre: issue docs, exposés. Environmental catastrophes, cover-ups, injustices all the way up to genocide. HBO’s Memphis Three muckrakers that helped free three wrongly convicted kids. Lefty takedowns of right-wingers. Right-wing takedowns of lefties (less common). Sometimes these movies break through, but they’re bitter medicine.

3. Personality-driven investigative journalism (and essay). Michael Moore as a lumbering prosecutor. Morgan Spurlock eats at McDonald’s, gets fat, barfs.

4. Errol Morris, or Anti-Vérité. Stylized reenactments and talking heads shot from a fixed perspective, as in The Thin Blue Line and The Fog of War, with Philip Glass music to provide momentum. Some purists don’t like how Morris makes ­implicit fun of his subjects. Others love how he lets liars hang themselves in front of our eyes.

5. Profile (individual). The biggest are celebrity-driven, in the A&E Biography mode, only more raw—Joan Rivers, Don Rickles, tragically dead comedians like Richard Pryor (Omit the Logic at this year’s Tribeca) but also laudable public figures (Jonathan Demme’s Jimmy ­Carter Man From Plains) and resonant weirdos (The Queen of Versailles, The Impostor).

6. Profile (place). Choose a city; chart its fall (Detropia). Towns with people doing odd things. Subcultures. The great Barbara Kopple (who straddles verite-individual-place lines). Les Blank, R.I.P.

7. Competition. Big these days. ­Pumping Iron is an early example, but Spellbound opened the floodgates. Chess teams, kid car racers, crossword-puzzle addicts, name a contest. Almost exclusively American, as we’re so competition crazy.

8. Ken Burns. Mostly TV. Photos, archival footage, talking heads. Panoramic. Excellent when the camera roams around still photos to give the frame some dynamism. Your video apps give you a “Ken Burns” mode.

9. Archival (related to Ken Burns). A comer. Old footage creatively edited, with fewer talking heads or narration. More story-driven than many fictional films.

10. Diary/Memoir. Ross McElwee’s Sherman’s March inspired many of today’s doc filmmakers with its emphasis on real-time conflicts plus a big dose of (related) history. More cameras mean more docs with people chasing their crazy mothers around, as in Tarnation.

11. Odyssey/Mystery (related to Memoir). Tracking down a famous figure, as in Searching for Sugar Man, or the guy who swore in the outtakes of the Winnebago commercial. Catfish-style treks for strangers.

12. Performance. Concerts, musicals, and comedy, but sometimes with talking heads (or Talking Heads, as in Stop ­Making Sense). Can be related to Profile.

13. Arty/Collage. Chris Marker is the gold standard. Meditations on places, usually too impressionist to be commercial. Koyaanisqatsi gives it a head-trip soundtrack. Much love for the current Leviathan.

14. Nature. Penguins, migrating birds, underwater creatures with James Cameron in Imax. Cute but eerie (even primordial) sells.

15. Meta. What is truth? Can it really be documented? Brace yourself for Sarah Polley’s coming Stories We Tell, which blurs the lines between myth and reality.

16. Prank docs. The hilarious Exit Through the Gift Shop, which is almost too good to be true. Joaquin Phoenix ­pretending to be nuts.

17. Mockumentary. Not docs, but they have an impact. You can’t watch a rock-band profile without thinking of This Is Spinal Tap.

And then there’s the phenomenon of fiction films’ looking more and more like docs and docs like narrative-based fiction films. For Hollywood faux realism, you get shaky handheld cameras and the mixing of actors and real people, as in Richard Link­later’s Bernie. The mumblecore genre tends to be improv-based, pointedly fumbly. The Tribeca folks sent me a batch of docs to screen on DVD, and I watched one for fifteen minutes before I realized they’d slipped in a fictional feature.

Which of these subgenres is hot right now? It’s cyclical. Top sales agent Josh Braun, of Submarine Films, says that seven years ago, after the Moore and Spurlock moneymakers, companies were snatching up docs for the high six figures, and most tanked. But then came successes like Food, Inc. and profile docs ­Valentino: The Last Emperor and Jiro Dreams of Sushi (still going strong as a digital download) and distributors were back in again—although more realistic about their upside. What’s interesting, says Braun, is that docs have “more of a fallback plan” than, say, indie features with no star power. If you can’t get a ­theatrical release, there are multiple TV possibilities. There’s iTunes, Reddit. Over at online streaming service SundanceNow, Thom Powers curates a documentary club where you pay a monthly fee and have access to the sorts of films you can’t see in theaters.*

Not that there’s much money. Ryan Harrington, the director of documentary programming at the Tribeca Film Institute, says, “I fund about 40 to 45 filmmakers a year. And usually my first question to them is, ‘Do you want fame and fortune, or do you actually want to make a difference with your film?’ ” Most want fame and fortune. And a theatrical ­release. And reviews from top film critics. And awards. HBO’s Nevins chooses a few docs a year for theatrical release on the basis of whether they have a shot at the Oscar.

Beth Janson, executive director of the Tribeca Film Institute, disagrees with twentieth-century “laudatory” strategies like Nevins’s: “Right now we’re hanging onto these old-fashioned banners, but how does that relate to the ‘Kony 2012’ video?

“The most exciting stuff is popular,” she says. “And these projects typically live online. And that’s very exciting. The documentary world was in danger of, I call it, the ‘circle of people who care.’ So you have fairly elite, liberally minded people who go to festivals, and they sit in a dark room and they learn something new about a horrible injustice in the world. But those are already people who care about horrible injustices in the world.

“If you’re talking about bullying, how are you going to reach the crowd where bullying resonates the most? The 13-year-olds of the world? For us, that answer is in technology. So apps, and online experiences, Facebook games. That’s not even the future; it’s what’s happening now.”

In June, the TFI will launch a “media-impact assessment group” with the MIT Doc Lab and the Fledgling Fund to measure the impact of filmmakers’ efforts. Which is, Janson admits, what for-profit marketing people have done for years, but not so much high-minded doc-makers.

How that will work is tough to predict. But I’m for anything with a chance to break through the noise. Sometimes I can’t believe how little impact the docs I love have on the national conversation. To pick one example out of, believe me, hundreds, there’s Alex Gibney’s Client 9: The Rise and Fall of Eliot Spitzer, which paints a credible portrait of a politician forced to resign not just because his brain was in his crotch but because some of the biggest dogs on Wall Street—whom he’d prosecuted for alleged financial ­chicanery—put a full-time tail on him as governor. That’s a huge deal. Why doesn’t everyone know about it? Why didn’t it break through the way, say, so many Fox News talking points break through?

A Greenpoint filmmaker named Sean Dunne is one of a new, impatient breed of doc directors, making fast and entertaining drive-by shorts that he posts on his website ­veryapeproductions.com. Two of them, The Archive and American Juggalo, quickly went viral. The Archive got into Sundance, where it won a prize. But he wasn’t as elated as you’d think. “Hey, 100,000 people looked at this on the Internet in the past month,” he remembers thinking. “And I went out to Sundance and spent a bunch of money to get it there and played to audiences of 200 people.”

Tribeca is screening Dunne’s first feature, Oxyana, about a West Virginia town in which much of the population is addicted to prescription drugs. He raised $51,000 via Kickstarter and the rest from private investors. Sales reps will try to sell his film somewhere, and he knows he has an obligation to pay people back. “But honestly,” he says, “I want to put this on the Internet today for free and say, ‘Here. Let’s talk about this.’ And I’m ready to go make the next one. This whole part of the process makes me really uncomfortable. I just want to keep making films.”

Of course, Dunne has a day job—he ­supports himself making commercials. Doug Block, of the D-Word site and the terrific autobiographical documentaries 51 Birch Street and The Kids Grow UP, says Dunne’s attitude “drives me a little crazy. Because that’s like saying documentaries are a hobby.”

How does Block support his family? He has a business shooting weddings, vérité style. When I suggest that couples would be lucky to have a photographer like him, he says, “Maybe not.” He’s finishing a doc called 112 Weddings, in which he intercuts footage of those big wonderful wedding days and interviews with some of the couples now. After a few years of marriage, he says, their body ­language is very expressive. A short preview confirms that the honeymoons are over.

Which brings up something else that makes documentaries more lively these days: a culture of exhibitionism. When Dunne went to West Virginia to meet addicts, he got a few death threats. But his actual subjects were surprisingly open. “The second the cameras are rolling,” he says, “they’re not only talking to you, but they’re saying, ‘You want to see some drugs? I have some right here. Actually, I’m going to do them on camera right now.’ And there’s no prompting by me.

“I think that this country has just become a constant ongoing audition for a reality show.”

And there will be no shortage of documentarians to capture it all, plumb its depth, make stories out of it, and try to turn a fleeting reality into something that will endure.

*This article originally appeared in the April 22, 2013 issue of New York Magazine.

* This piece initially inferred that Thom Powers curated an online documentary club for Sundance when he does so for SundanceNow, which is not associated with the Sundance film festival.