A few years ago, a stranger snapped a photo of Mozilla social strategist Liz Hull from behind. They posted it to Twitter and tagged her handle: “Ooh, I see Liz!” she recalls the post saying. Their intent may have been innocent, but the experience for Hull was unsettling. “I realized I need to not have my location on any social media,” she says. It was the first time she’d given considerable thought to taking online security seriously.

Today, Hull and her Mozilla co-workers have gathered little more than a dozen women, from a variety of backgrounds with varying experiences and knowledge about tech and the internet, to pursue better solutions for safety online.

When I meet the group, they’re filtering into a starkly white event space in midtown Manhattan. Half of the room is set up with snacks and a wide area where the physical portion of the evening will take place. The other half is a neat circle of chairs. Guests are expecting a small lecture on how to be safe online, followed by a grueling hour of self-defense for life offline.

Privacy and online security have been creeping toward the public forefront for years. In 2017, issues surrounding these topics make headlines on a regular basis. Net neutrality is on its way out, social media is more influential than ever, and not even the president may practice good security. But it’s also a heightened time of activism and protected communications, where the user base for protected messaging services like Signal is on the rise.

Hull says that as security issues have become more mainstream, there’s an increased need for education and empowerment. This particular program is specifically meant to teach women, who are often the target of vicious online attacks. “As activism became more a part of people's lives, and it was something people were talking about, we saw a need to get in there.”

"The internet isn't a healthy place,” Hull says, “unless everybody feels safe to create, to communicate.”

Most of the event is led by Amira Dhalla, head of the women and web literacy programs at Mozilla. Dhalla has spent a great deal of time working with other women and learning their stories of online harassment: threats, attacks, crude insults, slurs, being subjected to images or videos they don’t want to see. Posting someone’s address or phone number is on the more extreme side of the spectrum, but women receiving abusive messages on their social media or in their inbox happens every day online.

“It's starting to actually frighten me that this is the world we live in that is pushing women to not want to interact online and not want to be online,” Dhalla tells The Verge. Her goal is to encourage people to understand that privacy and security is something all people are entitled to.

“We know to have the things we want, like openness and collaboration and equality and all that sort of stuff, people have to feel safe online ... If you don't have that, then you're going to have large groups of the population just not engaging online. And then you're just going to have one type of people and it's not going to be an inclusive setting.”

“you need to understand the spaces you're in, whether they're real life or digital life.”

My first reaction to the event was, frankly, bewilderment — first, about why a company best known for a web browser was tackling online safety, and second, the concerning juxtaposition of online and offline safety. Learning how to protect yourself from harassers and trolls online is a crucial, albeit deflating, part of existing online; it’s hard to grasp how easily you can become a target until you’ve seen or experienced it firsthand. Having to physically fight off an attacker — who may or may not have gotten their start as an online stalker — is a much more frightening implication.

But Dhalla says that learning to protect yourself online should be taken as seriously as physical safety. “You walk every day in a crowd, sure, but you're online even more,” she says. “Understanding how to protect yourself in both realms is important.”

“I don't want to say you need to protect yourself more online or more offline,” Dhalla adds. “I think you need to understand the spaces you're in, whether they're real life or digital life.”

The burden of protection shouldn’t have to fall directly on women, but women are frequently the target of online attacks. Dhalla’s goal is to help participants feel empowered. Teaching online safety and privacy to a group of people, any group of people, is not without its challenges. There is a basic question of literacy, understanding how and why and what is involved with protecting yourself online. And each person’s experience is unique. Their contact with harassers is likely dependent on factors like their job, age, location, race, gender, or general interest in participating on platforms like Snapchat, Instagram, or Twitter. For some, using a service like LastPass is the first and final step they’ll need to take; others might go as far as setting up VPN servers and locking down social accounts.

The class itself is mixed in this regard, ranging from women with high knowledge of how to stay safe and those who were unfamiliar with the concept of doxxing, or removing personal information from third-party sites online. One woman told me earlier in the night that she felt naive about the internet and how to protect herself; another had recently started practicing basic safety steps, like covering her computer’s built-in camera with a post-it note. Organizers pass out a sheet with basic tips for protection: turning off tracking on social media, not clicking on unrequested email links, two-factoring accounts. The session involves a lot of interaction, with Dhalla hosting a “true or false” quiz on a variety of security topics (“Can Macs get viruses?”) and asking women to share their experiences.

These are the kind of first steps most internet-savvy people are likely to already know. Dhalla tells The Verge that when it comes to teaching security, the best way to start is… small. “I don't expect anyone in this room to set up a VPN,” she says, despite listing it on her handout. “But I do want you to know that there are options, and I do want you to know that something as small as covering your webcam is the first step to you being empowered in your digital life.”

Chaos ensues for a few rounds

As the session wraps, the group meanders over to the large, empty space on the other side of the room. This is where the physical portion kicks in. Mozilla hired a New York Krav Maga instructor to pass on some basic tips about defending yourself from bodily harm, or worse. The instructor is frank about the possible outcomes, which women rarely need reminding of. Everyone partners up as he encourages us to lock grips — one hand on the other person’s shoulder, one on their arm — and do our best to get behind the person without breaking our own hold. He counts down from 10, and suddenly the room is filled with the scuffling sounds of women grunting and circling like teenage crabs at a school dance.

Chaos ensues for a few rounds, punctuated by a polite swapping of partners. Over the course of the hour, we’re instructed on how to position ourselves, techniques to most effectively slam someone in the crotch, how to gouge someone’s eyes, and — if you do in fact successfully get behind a person — how to bring them to their knees and successfully choke them into passing out. Before each round with a new partner, participants happily greet each other and extend a hand to shake. A woman introduces herself and I return the cheerful greeting; not even 30 seconds later I’ve accidentally knocked her to the floor by pushing a little too aggressively on her hip. I pull her up and we start again.

The Krav Maga session is certainly more thrilling than 45-minute circle talk; it’s exhausting, too, but in a more obvious, physical way. By the time it ends, everyone is sweating and panting heavily. Throughout the entire hour, it was impossible not to participate, not to engage in learning self-defense tactics. That’s the kind of hands-on experience that online security so desperately needs. Something as immediate and tangible and real as being knocked to the floor.

“When you talk about privacy and security, most of the time people are like, ‘Oh this is kind of boring,’” Dhalla says. “But it shouldn't be. It's a huge issue, and it's a huge topic to have a conversation on. We want to bring it in on a fun, lightweight type of way where people can understand and grapple with it and see it more as a social mainstream thing that is like engaging vs. the latter.”

Of course people hold physical harassment in a higher regard; it’s a visible danger, a clear and obvious one. In the days following the class, purple and blue bruises swell up around my arms and legs where I made repeated — and consensual — contact with women I trained with. But the bruises from the online harassment I’ve experienced are invisible. They become inflamed, and when untreated, spread quietly inside my head. After years of existing in my own professional spotlight on the internet, I’ve learned how to heal and sometimes even ignore the racist or sexist slurs, the rape threats, the intimidation meant to cow and silence me. I’ve also never forgotten any of it. Online harassment is real danger. It triggers a physical reaction in you, whether or not your harasser is standing in front of you.

Dhalla says that confidence is key. By encouraging women in the physical sense — inspiring them to be proud and confident and strong — she believes it will help them to take control of their lives online, as well. But there remains an onus on companies and members of tech to do better as well. Dhalla says that Mozilla hopes to continue these events nationwide, and eventually with its partners internationally, in addition to the the privacy and security tips it offers online. It’s already hosted another real-life event focused on privacy and surveillance, a pop-up last year called The Glass Room.

“It's just not enough now to say we want to help get women and girls into STEM,” Dhalla says. “We need to support them when they're there.”