HBO has taken heat over the years for the perceived arrogance of the slogan “It’s not TV, it’s HBO.” But now it’s at least a little bit true. Hidden away on HBO Go, the online video site for the cable channel’s subscribers, are four shows that aren’t TV, although they might have been.


Among the site’s complete runs of HBO television series like “The Sopranos” and “Game of Thrones,” comedy specials and movies, it’s easy to miss the short-form videos grouped under the heading HBO Digitals. All are comedies of one kind or another and were either developed as possible TV pilots or commissioned directly for the Web from artists who interested the channel. Mostly featuring young performers doing variations on relationship comedy, they could be seen as test runs for the next “Girls.”


The one show that doesn’t fit that mold is “Brody Stevens: Enjoy It!,” starring the contentious comedian Brody Stevens and his friend Zach Galifianakis, who appeared in the HBO series “Bored to Death.” Consisting of 16-to-17-minute episodes, it’s somewhere between documentary and full-on mockumentary, incorporating scripted scenes (written by Mr. Galifianakis) and animation into its profile of Mr. Stevens, an underground favorite with an aggressive style and offstage issues that include staying on his psychiatric medications.


“Brody Stevens” is inventive but feels like a show you might see on a lot of comedy- or reality-oriented cable channels, and despite the presence of Mr. Galifianakis, it’s less interesting than the other HBO digital offerings.


The slightest of the projects is “Garfunkel and Oates,” 3- to 6-minute videos by the Los Angeles comedy and singing duo of that name. Garfunkel and Oates are the actresses Riki Lindhome and Kate Micucci (Shelley on “Raising Hope”), and this series consists of absurdist sketches, sweet-faced but dirty, on subjects like the misogyny of the comedy business and the awfulness of pregnant women. They’re charmingly acidic and fly by with the help of peppy songs like “Pregnant Women Are Smug.”


The last two shows, “Single Long” and “The Boring Life of Jacqueline,” are ambitious scripted projects (though “Single Long” feels largely improvised) in 15-minute episodes that milk comedy from the plight of the penniless millennials, though in very different ways.


“Single Long” is set in Chicago, where Pete (Ed Hausman) and Isaac (Jack Lawrence Mayer) are roommates so poor that Isaac fears starvation. Rather than looking for work, they’re developing a dating Web site with the terrible name Single Long — it’s supposed to remind you of singalong — where bruised romantics like themselves can share too much information through videotaped interviews. A spiky would-be stand-up comic, Ayla (Sarra Jahedi), joins the Single Long team after Pete becomes smitten with her at an open-mike night.


The series, created and written by its three stars, is essentially a low-budget feature film in seven parts, more sprightly than mumblecore but with less energy than an indie romantic comedy. The comedy of miserableness, awkwardness and meandering conversation is pretty familiar, but there are lines that pop in each episode of “Single Long.”


“I know that she’s my girlfriend in my head, in a way that I don’t really need confirmed by what happens in the world,” Pete says of the ex he won’t let go. Sitting on a castoff couch in an alley (it still needs to be carried upstairs), Isaac says with great satisfaction: “We’re living in Chicago. Basically no money. I’d call this surviving.”


“Single Long,” which features an engaging performance by Ms. Jahedi, would be perfectly respectable if it didn’t make the fatal, though common, mistake of going sentimental at the end of its seven-episode run, as a disconsolate Isaac turns the Single Long camera on himself and records a teary, mopey statement of purpose: “I just want to meet somebody better than I am.”


“The Boring Life of Jacqueline,” which has generated the most buzz of the HBO Digitals series, also ends on a hopeful note, but it hardly registers given the overall comic grotesquerie and emotional nihilism. Where “Single Long” takes the usual course of focusing on smart slackers, “Jacqueline” is about a delusional, narcissistic dope.