Entertainment

Dear diary . . .

There are many questions yet to be answered in the whole David Letterman affair, not least of which is: Who keeps a diary? Other than 12-year-old girls, that is.

Actually, we found a number of New Yorkers who daily put pen to paper or fingers to keyboard in what they claim to be a helpful, often therapeutic practice. And while none boasted of Stephanie Birkitt-style steamy entries, they say they get plenty personal.

One East Villager, 43-year-old Nick, said he writes down events because he’s forgetful.

“It’s also slightly therapeutic, but the notes are mostly for reference and to solidify my existence,” says Nick.

As a comedy writer, Caroline Waxler keeps diaries to find material.

While she may draw from it, she has no plans to publish it. “I’d be mortified if anyone read [my entries] in their current form.”

So why run the risk?

“It’s also a cheap shrink,” she admits.

It seems that while a “diary” tends to be the Birkitt-y province of dating melodrama, grown-ups keep journals.

“You’d be surprised at how many people are journaling with a pen and paper,” says David Nadelberg, the founder of Mortified, a site of teenage diary entries (getmortified.com).

And even in this exhibitionist age of Facebook, Twitter and blogs, the privacy of a journal offers something unique.

“The most sincere, personal blogs are never going to capture the vulnerability and intimacy you get with things that are intended for an audience of one. And that one being yourself,” says Nadelberg.

But the threat of exposure — even in the face of the Letterman scandal — doesn’t seem to faze dedicated diarists. Lots of people we spoke to simply don’t bother encrypting digital journals or stuffing their Moleskin diaries under a mattress.

Nick used to leave his laptop on the living room table, where his partner could have easily accessed it.

“If I were having an affair, I might have encrypted it, but I wasn’t,” he says.

And if someone found it?

“There is plenty of embarrassing stuff. It would be bad, but not in the ‘I’m f – – – ing Letterman,’ sense,” he says. “There’s nothing on it that would destroy someone else’s life.”

Waxler doesn’t encrypt or hide hers, either (beyond password protection), but she says that if she were living with an investigative journalist, as Birkitt was, she’d lock her scribblings up in a safety deposit box.

“Clearly she [Birkitt] wanted something to be found out,” Waxler speculates.

When Williamsburg resident Randy, 31, was a teen, his mom would rip out illicit pages of his journals. Today, he still leaves them out.

“I don’t have any great secrets,” he says.

And Sara doesn’t let anyone find hers now, though she writes a journal with the thought that it will be read someday. She even uses a thesaurus.

“If I cheated on my boyfriend, I wouldn’t record it,” says the 32-year-old actor, who keeps her leather journals hidden deep inside her Greenpoint apartment and in storage. “And if I say something negative about someone, like my boyfriend, I’d make sure it’s countered.”

Today she can’t imagine anything worse than if someone discovered them. “In my fantasy, people would care,” she says. Her audience is for after she’s dead.

Of these diarists, only Sara has plans for her journals: She’s willed them to a friend to pass on to Sara’s future children, so they “will know I was there.”

For whatever reason she was keeping diaries, Birkitt probably didn’t expect her journals to end up as part of an alleged blackmail scheme and made public.

It’s an extreme version of what can happen.

“We all have an awareness that some jerk or parent will possibly pry through the pages of something we wrote, but we do it anyway,” says Nadelberg.

marymhuhn@nypost.com