is the author of “Dataclysm” and a co-founder of OkCupid.

Once upon a time, online daters were mocked as lonely losers, or worse. Not anymore. Today, at least 40 million Americans are looking for love on the Web. But that doesn’t mean we know what we’re doing. Like sex, love and attraction, online dating is an object of fascination and confusion. Some commentators credit it with helping singles feel more secure and confident, while others blame it for “ruining romance,” “killing commitment” and contributing to the rise of the hook-up culture. As the head of OkCupid, I worked diligently to untangle many of the misconceptions about finding love on the Internet. But some persist; here are the most common.

1. Men aren’t interested in women in their 30s (or, God forbid, their 40s).

The raw data is undeniable. While women generally prefer men around their own age, men are most attracted to 20-year-olds, period. That’s why the Daily Mail calls straight women over 45 the “plankton generation” — at the bottom of the romantic food chain. Time magazine editors found the notion of men dating women in their 30s so baffling that they invited 15 experts to explain the phenomenon.

But as I learned at OkCupid, men don’t necessarily end up dating young women, even if they think they’re gorgeous. Men on the site tend to message women closer to their own age; very few men over 30 actually reach out to 20-year-old women. And while it’s true that being older and single means you face a “thin” romantic market, both on the Web and off, the sheer scale of online dating mitigates this. After all, the best way to beat long odds is to take lots of chances, and even for older users, dating sites provide millions of romantic options.

2. Online dating is to blame for our hook-up culture.

It’s an all-too-common trope: Online dating has made casual sex easy but relationships hard. One somewhat hysterical Vanity Fair article recently claimed that sites like Tinder have brought on a “dating apocalypse,” with young men and women meeting online, getting together for sex, then never talking again. The Guardian warns that these sites have created a “throwaway dating culture.”

This is silly. People have always sought out casual sex — flings are key plot points in “Pride and Prejudice” (1813) and “The Fires of Autumn” (1942). One sociologist found that college-age students are having no more sex today than they were in 1988. In fact, online dating has made it easier for those seeking long-term commitments to find each other. Experts say that one-third of recent marriages in the United States started online. Those couples tend to be happier, too, research suggests.

3. Everyone lies online.

This assumption is so prevalent that MTV has an entire show, “Catfish,” devoted to investigating whether people in online relationships are representing themselves honestly to their partners. In one extreme example of an online lie, Notre Dame football star Manti Te’o was tricked a few years ago into virtually dating a woman who never existed.

But while it’s tempting to shave off a couple of pounds or add a couple of inches, studies show that online dating profiles are, fundamentally, quite honest. Gwendolyn Seidman, writing in Psychology Today, explains it well: “Online daters realize that while, on the one hand, they want to make the best possible impression in their profile, on the other hand, if they do want to pursue an offline relationship, they can’t begin it with outright falsehoods that will quickly be revealed for what they are.”

That’s not to say every profile is the gospel truth, of course. People do exaggerate, just as they do in person. OkCupid has found, for example, that men and women more or less uniformly add two inches to their height. In any human interaction, there will always be some amount of posturing. But online dating isn’t especially vulnerable to our collective weakness for self-flattering fibs.

4. Online dating is dangerous.

Grim stories abound. In 2010, Boston’s “Craigslist killer” was charged with murdering a woman he had met online (he later committed suicide in jail). In 2013, Mary Kay Beckman sued Match.com for $10 million after a man she met on the site came to her Las Vegas home with a knife and an intent to kill.

But despite the occasional bad press, the numbers suggest that online dating is very safe. OkCupid creates something like 30,000 first dates every day, and complaints about dangerous meetings are extremely rare. I remember only a handful in my 12 years at the company. Although there are no comprehensive numbers, executives with other sites report similarly low levels of abuse. Additionally, dating sites have taken steps to respond to concerns. Match.com, for example, now checks its users against the National Sex Offender Registry and deletes the profiles of anyone found on the list.

Online dating allows people to browse partners from their own homes. Compare that with meetings at bars or parties, where people might be a few drinks in when the flirting starts (studies show that alcohol use increases the risk of sexual assault). Also, people almost universally pick public places for their initial online dates: coffee shops, restaurants and the like. It’s very deliberate — after all, you’re looking for a partner through an interface — and that creates a safer environment.

5. Photos are the best way to tell whether you’ll be attracted to someone.

It seems obvious, right? This premise is so well-worn that sites like Tinder, Hinge and Coffee Meets Bagel offer little information about users beyond a collection of pictures and a two-line profile. “Online services enable a downright Seinfeld-ian level of superficial nitpickiness,” one Fortune article lamented. They’ve “given rise to a pick-and-choose shopping behavior that prioritizes looks more than ever before.”

In reality, how someone looks in a couple of pictures is no indicator of whether you’ll be attracted to them. That point was driven home for me during a small publicity stunt OkCupid ran to promote a blind dating app; we called it Love Is Blind Day. The premise was simple: For a day, we removed all the profile pictures on the site. Users howled — site traffic dropped more than 80 percent that day. But those who stuck around had much deeper and more productive conversations than normal. Replies to messages came fast, and dates were set up more quickly. We saw the same thing among people who used our blind dating app. A person’s attractiveness had no correlation with how well a date went. All in all, OkCupid worked better with no pictures.

The catch, of course, was that, without pictures to keep users happy, OkCupid would go out of business. So we turned the photos back on, giving people the dating experience they wanted: superficial, skin-deep and probably worse.

Twitter: @christianrudder

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