Flashback to 2010: Vine had yet to be released and was subsequently shuttered, the 4.5-by-2.3 inch iPhone 4 fit neatly in the palm of a hand, and internet celebrity Jake Paul was 12 years old.

A decade can revolutionize culture, and the 2010s changed the internet in ways that seemed unimaginable at the time.

As 2019 comes to a close, NBC News spoke with some of the people who helped shape the digital space as we know it, including meme makers, YouTube stars, viral celebrities and internet critics, many of whom have asked to be identified by the names they use online because of privacy concerns.

The Innovators

Jake Paul, 22, rose to fame in tandem with internet culture at the start of the decade.

Paul and his older brother Logan started their online presence with the now defunct video app Vine in approximately 2013, and eventually moved over to YouTube, where the pair has amassed gargantuan followings, controversies and fame.

”I would say my whole entire career has kind of grown with the growth of internet culture,” Paul said in an interview. “It’s just crazy to see how fast everything changes and moves, and growing up in it has been crazy.”

He said over the last decade he’s noticed social media and the fame it provides become more accessible to a larger number of people.

“So the content has really changed, and you have to be able to move and adapt,” Paul said. “I started off on Vine making six-second videos that were short, comedic and highly consumable and viral. From there Vine died, moved on to Facebook … and eventually saw a huge gap in YouTube where I didn’t think anyone was putting in that much effort.”

That inspired him to move his content to YouTube, where Paul said he feels he helped revolutionize the type of content being shared, like his episodic videos, which encouraged followers to come back and check in with the cinematic universe he was creating. Others take issue with that, however, and have criticized Paul for the amount of self-promotion in his video, including hawking his merchandise and tour dates.

“Now, we see on YouTube … vlogging isn’t a thing anymore. People don’t care about everyday videos. They just want to see the quality of the videos go up … and you see the short consumable content coming back on TikTok,” he said. “The evolution of where things are going is not known to anyone. You just kind of have to ride the wave.”

Paul’s internet career hasn’t all been smooth sailing, though.

In 2017, he made headlines for causing a ruckus in his Beverly Grove, California, neighborhood, and he later moved. He’s also been accused of uploading content considered inappropriate for his younger audience, like a series on his channel about killer clowns who kidnapped him and his girlfriend.

“It’s hard growing up living under the spotlight. I lived my 17- to 22-year-old life with millions of people watching every little thing I do. So if you make a mistake, it’s under a microscope,” Paul said.

He also said the scrutiny often wasn’t fair, and that while the decade has been marked by positive improvements like greater access to knowledge via YouTube, the worst development of the decade was the rise of cancel culture.

“I see someone getting canceled on Twitter every day,” Paul said. “I think there’s a lot of negativity online.”

But not everyone who has attained internet fame over the last decade has faced widespread backlash or criticism.

Justine Ezarik, 35, who goes by iJustine on YouTube, has been making videos since 2006 and largely makes tech-related content.

Ezarik’s content has been viewed more than a billion times, and she said the biggest change she’s noticed over the last decade is the ease with which content is made.

“Back when I was doing it, there were no cellphones you could post or edit and I think the technology has changed and made it easier to create content. But it’s also made it a little more difficult because that barrier to entry is so easy,” Ezraik said.

For Ezarik, Paul and scores of others, YouTube has become a full-time job.

“When I tell people I make YouTube videos, they don’t laugh at me. They say, ‘That’s so cool!” Ezarik said. “It’s definitely more mainstream and people understand it.”

The Meme Makers

Through YouTube, Twitter, Reddit and now TikTok, to name a few, memes have arguably become the reigning language of the internet and social media.

Two of the most prolific creators of memes over the last decade are Dr Grandayy and Dolan Dark, who both asked to be identified by their internet personas.

Dolan Dark said he began creating memes on a Facebook page in 2011 before moving over to Twitter and YouTube, while Grandayy has been making memes on YouTube since approximately 2016.

The biggest shift in memes over the last decade, according to Dark, is the sheer volume of content.

“In like 2010 to 2012, there were probably, like, 10 or so big memes for the entire year,” Dark said. “Now, in 2019, you'll have 10 big memes all happening in the same month.”

Grandayy added that they’ve also become more mainstream, giving each one a shorter and shorter lifespan.

“Basically memes are funny, relatable, easily created and even more easily shared,” Dr Grandayy said. “The combination of all these factors makes them a very good medium that almost anyone can find entertaining. Memes are simple but can tell a more complicated joke, or have obscure references, and all of this in just one image — or video in some cases.”

When asked to identify the biggest meme of the decade, Dr Grandayy cited “We Are Number One” from the Icelandic children's television series “LazyTown,” sung by actor Stefán Karl Stefánsson’s character Robbie Rotten.

The meme is often remixed with different audios and visuals, and Stefánsson embraced the meme, giving it even more leverage, before his death due to bile duct cancer in 2018.

Dolan Dark said the meme of the decade was Doge, a slang of “dog” often associated with an image of a Shiba Inu.

“If you're already sick of memes, sorry to say, but the next decade will be even bigger,” Dolan Dark said.

The YouTubers

If you were to ask Nerd City, a YouTuber who creates methodically researched documentaries about internet culture and stars, when the digital space began to lose its authenticity, he would point to the beginning of the 2010s, when Facebook started to allow people to untag themselves from photos.

“Regular folks started protecting themselves like big important brands; profiles became hubs of self-curated propaganda,” Nerd City, a leading critic of both internet culture and YouTube, said. “It wasn't always like that.”

As a wealth of personalities have sprung to superstardom on YouTube, Instagram and Twitter over the last decade, Nerd City has had plenty of content to critique. Examples of Nerd City’s videos that have drawn millions include deep dives into the “lies of Jake Paul” and a look at how Instagram influencer Jen Selter gained popularity.

“They each have qualities that people find interesting, and they haven't hesitated to put themselves front and center in daily content,” Nerd City said. “Frequency has been the magic recipe on social media, because it lets viewers build habits around the content.”

Content review channels, which critique and review other videos on the platform or content elsewhere on the internet, have exploded in the last decade.

It was Philip DeFranco, a news commentary channel, and Nerd City, who almost simultaneously made news in 2017 when they shed light on the channel DaddyOFive, in which parents appeared to abuse their children under the guise of “pranks.”

In Nerd City’s opinion, what has bolstered the popularity of channels like his and differentiated it from mainstream media over the last decade is the ability for viewers to help shape the coverage content creators explore.

“I think part of what makes self-published internet content interesting is the way viewers participate ... If there's a community around a channel, they'll try to steer it towards another interesting place to go, and that's pretty helpful,” Nerd City said.

Another direction creators have taken is toward cringe content — a genre defined by a so-bad-it’s-good quality that makes it hard to look away.

“There’s so many people making terrible content today, it’s hard to name the cringiest,” said Kurtis Conner, 25, another content reviewer who takes a more lighthearted and comedic approach to his videos. “I feel like that word gets tossed around a lot these days, and I think it’s lost a bit of its meaning, but I’d have to say the ‘e-boy’ content was the stuff that made me the most uncomfortable.”

E-boys came about at the tail end of the decade with the rise of TikTok, and are a sort of evolved emo teenager, with colorful hair, dangling earrings and a look that loosely resembles anime characters.

“There’s something very unsettling about a moody teenager choking their phone while trap music plays in the background,” Conner said, referring to the Southern-based hip hop music. “Didn’t like that one bit.”

Conner, who has been a part of the YouTube community since 2008, said when he looks back at the decade, what defines it to him isn’t the platform he currently uses, but the one he used in the past.

“For me, I would have to say Vine was something that really catapulted video content and meme culture into popularity,” Conner said. “Some of the most iconic moments that happened online in the past 10 years were all Vines … I feel like most of the things quoted today were all from Vine.”

But when he looks to the future, Conner said it’s hard to pinpoint what the next big thing will be as the new decade rolls in.

“I’d like to think that because this is my job, I have some sort of idea about where the internet is going, but I don’t think anybody does,” Conner said. “It changes every single day and the most you can really do is try to adapt.”