Three days after a gunman murdered 17 of her schoolmates and teachers, an 18-year-old survivor took to the stage at a gun control rally and delivered one of the most powerful speeches in modern American history. Emma Gonzáles had to stand on boxes just so she could reach the microphone, but that didn’t undermine her authority, as she told the “politicians who sit in their gilded House and Senate seats funded by the NRA” that high school students “call BS” on them. A few days later, she spoke at another rally, and led a silence of six minutes – the precise duration of the shooting spree.

If she’d done all this before the advent of social media, she might have become a local celebrity. In 2018, though, it was different. Gonzáles’ name was trending on Twitter within hours of her first speech. By the end of her second, she was seared onto America’s frontal lobe. She made the cover of Time magazine, she had attracted 1.6 million Twitter followers and had cemented herself as the buzz-cut figurehead of the US’ gun control movement. It’s safe to say that her sudden fame has changed her life profoundly, and may also alter the lives of her fellow Americans and leave a legacy remembered for years to come.

Such is the transformative and perhaps alarming power of social media. Russell Horning, 17, is often credited with inventing the dance move “flossing” after he performed – with a rucksack on his back – on Saturday Night Live alongside Katy Perry in 2017. It became a global dance craze and Horning, who is now nicknamed ‘Backpack Kid’, has the world at his feet. He’s since dropped a music album and plans to add ‘movie star’ to his resumé, too. (He’s also suing the makers of videogame Fortnite for stealing his shapes, so that could also prove to be pretty lucrative.)

These are the success stories. But not every accidental social-media legacy is made equal. Lest we forget the angry redhead who posted a diatribe on YouTube denying a claim in the South Park cartoon series that “gingers don’t have souls”. He suffered online and offline bullying on a hellish scale; something we’re sure he’d rather forget than use to forge a place in the hall of Internet fame. Thanks to websites that enable social shaming, this kind of thing is common, says Dr Crystal Abidin, author of Internet Celebrity: Understanding Fame Online. “There are so many cases of internet vigilantes, where people who thought they were being helpful chasing down perpetrators or trolls, actually end up misidentifying people.”

So dreams are made or shattered online in minutes. Just one moment on social media has the power to transform a person’s life. That is, only (mostly) if they want it to.

Zeddie Little responded to his 15 minutes of fame in the spotlight differently. The handsome marathon runner, who, at just the right moment, flashed a swoon-inducing smile at a photographer, could have, at the very least, leveraged his new found fame to promote his purported PR aspirations. He became known as “Ridiculously Photogenic Guy”, after countless memes sporting his face flooded the Internet, but he didn’t seek any wealth or further fame. “That was quite an unexpected move,” says Dr Abidin. “Most of the time you see people try to milk it, but he was happy with whoever he was.”

This sudden rise to international fame might seem like a new phenomenon, but it’s not, explains historian Leo Braudy, who says digital social media is simply “the latest technological amplifier of both worthy and trivial action”. Braudy, who’s the author of The Frenzy of Renown: Fame and its History, reminds us of the noted pickpocket whose only claim to fame was robbing Oliver Cromwell, and yet he’s still remembered to this day. More recently, he points to the Guinness Book of Records, which spurs chancers to seek notability through “trivial accomplishment” such as having the longest beard.

Sure, none of these examples is as significant as Gonzáles’ achievements, but there’s no denying that social media now has the power to create even accidental legacies that, in many cases, will live on for decades – if not centuries – to come. Perhaps we are all one poignant speech, energetic dance move or hilarious YouTube video away from life-changing fame.