In 20 years, YouTube says more than 20 billion videos have been uploaded. Photo by Markus Winkler/Unsplash

Technology

YouTube Turns 20—How Have Its 20 Billion Videos Changed Us?

BU faculty experts: the social media platform has impacted our mental health, helped small businesses, artists, and musicians, birthed a do-it-yourself generation, and exposed us to dangerous misinformation

What started with a grainy, 19-second video from the San Diego Zoo on April 23, 2005, has transformed everyday life—in good ways and bad. In the 20 years since YouTube launched, 20 billion videos have been uploaded to the social media platform, the average person now spends almost 50 minutes a day watching the content, and the most popular YouTube video, called “Baby Shark,” is of a couple of singing kids with 348 million views. What has this video revolution taught us?

Yes, videos of crazy cats, kooky comedians, and cute babies are as popular as ever. And yes, the platform unleashed an entire generation of do-it-yourselfers who think they can suddenly engineer their way through any problem. YouTube has also spawned celebrities, like right-wing podcaster Joe Rogan, Hot Ones host Sean Evans, and of course, Mr. Beast. But the platform is also filled with dangerous disinformation about medicine, mental health, crime, and politics, to name just a few subjects. 

As YouTube celebrates turning 20, BU Today reached out across the Charles River and Medical Campuses to ask a range of Boston University faculty experts for their take on its impact on society.

Do-it-yourself
Tasker Smith, senior manager, BU Engineering Product Innovation Center (EPIC)

Our educational mission in EPIC is to help students develop the technical skills to tackle a variety of design challenges. Guided, in-person instruction is an essential part of learning technical skills—but in my opinion one of the greatest skills we can teach as educators is the ability to learn new skills.

YouTube has revolutionized skill development in a couple of ways. Quickly searchable and highly specific content makes technical knowledge accessible to virtually anyone with an internet connection. Where once tackling a complex project required specialized training, hard-to-find manuals, or technical expertise that was often difficult to find, today detailed tutorials, firsthand demonstrations, and on-demand troubleshooting advice are available within seconds. In addition to instruction, these instructional videos are commonly paired with links to part numbers that can be delivered overnight due to the staggering efficiency of services like Amazon that will deliver parts to your doorstep quickly.

Beyond simply providing technical instruction, YouTube also bolsters self-confidence—arguably the most essential ingredient for successful project execution. Watching others methodically break down tasks, overcome challenges, and share their problem-solving processes not only delivers clarity of process, but also inspires viewers to believe they can learn, adapt, and succeed. Successful builds depend not just on technical know-how, but equally on the builder’s willingness to experiment, persevere, and learn from mistakes. YouTube has helped foster a global culture where trial-and-error is celebrated, knowledge is democratized, and anyone with curiosity and determination can bring even the most ambitious projects to life.

Health (mis)information
Monica L. Wang, associate professor of community health sciences, BU School of Public Health

YouTube has profoundly reshaped how people access health and medical information. On the positive side, YouTube has democratized health education, offering free, widely accessible resources like exercise videos, healthy cooking demonstrations, stress management, and first-aid training. For many, especially those with barriers to healthcare access, these resources have provided valuable support for preventive care, wellness, and everyday decision-making.

At the same time, YouTube, alongside other media channels, has become a major conduit for health misinformation (health-related claims that are false, inaccurate, or misleading based on the best available evidence to date). Research shows that videos promoting inaccurate or misleading health claims, from vaccine myths to unproven treatments, often elicit more engagement than evidence-based content. This is deeply concerning since misinformation spreads faster than the truth (up to six times faster, according to some studies) and undermines public trust in science, medicine, and public health. While YouTube has taken steps in recent years to elevate credible sources and remove harmful content, the challenge remains: the platform’s algorithms prioritize engagement over accuracy, making it easy for misinformation to flourish.

The way our information landscape has evolved reveals a critical truth: sharing accurate information is necessary, but not sufficient. To meaningfully counter health misinformation, we must also focus on making evidence-based content engaging, accessible, and relevant to a wide variety of audiences.

All those ads!
Garrett Johnson, associate professor of marketing, Questrom School of Business

YouTube revolutionized digital advertising by enabling businesses of all sizes to target audiences with machine learning. This access fueled the rise of direct-to-consumer brands like Dollar Shave Club and Glossier. Our analysis of 432 randomized experiments shows that the median campaign, often involving YouTube ads, lifts advertisers’ site visits by 17 percent and conversions by 8 percent. These causal results help quantify what marketers have long intuited: YouTube is not just a venue for brand awareness, but a measurable driver of business outcomes. For a deeper look at YouTube’s fascinating history, I recommend the book Like, Comment, Subscribe by Mark Bergen.

YouTube’s ad model also supports its content ecosystem. Perhaps no example illustrates this better than Harry and Sona Jho, the husband-and-wife team behind the “Mother Goose Club” channel. The Jhos joined YouTube early because they saw a gap in quality, appropriate content for their children. With ad revenue from YouTube, the Jhos built a global brand in early childhood education, exemplifying how creators across categories can sustain their work through the platform.

A pivotal moment came in 2019, when YouTube paid a record-setting $170 million Federal Trade Commission (FTC) fine under the Children’s Online Privacy Protection Act (COPPA) and removed all personalization for kids content, including personalized ads. Our research finds this “COPPAcalypse” triggered a 13 percent decline in kids content production, a decline in views, and a shift by creators away from child-directed material. In sum, the history of YouTube reveals that even small policy shifts can ripple across industries, reshaping how businesses grow and creators thrive.

Who goes viral?
Gianluca Stringhini, professor of computer engineering, College of Engineering

YouTube revolutionized the way in which people consume online information. It made streaming videos look seamless and made searching for video content easy. Before streaming websites, people had to download video files in order to watch something, which was very cumbersome. And 20 years later, YouTube is still one of the main platforms that people gather information from. Even on other social media sites, YouTube links are prevalent. Video information is more immediate than text, and many people prefer to consume it to get information.

Democratizing the access to video information enabled anyone to post content and make it go viral. We’ve seen famous performers start their career on YouTube. At the same time, the information posted on the platform is often not vetted, and this exposes people to misinformation. The problem gets particularly worrisome when we consider that YouTube is powered by a recommendation algorithm, which recommends what video you should watch next based on your history and on the videos that people with similar interests watched. This carries the risk of having users being recommended to watch misleading videos without having explicitly searched for them, which only amplifies their reach. YouTube is constantly working to make its platform and its recommendation algorithm safer, but this is a cat and mouse game.

YouTube Shorts shortens our attention span
Seungbin Oh, assistant professor, mental health counseling and behavioral medicine, Chobanian & Avedisian School of Medicine 

Every major technological shift brings both extraordinary opportunities and unintended consequences—and YouTube, over the past 20 years, has been no exception. It has transformed how young people engage with the world, offering unprecedented access to creativity, information, and community. Yet at the same time, it has also profoundly reshaped the mental health landscape, especially for adolescents and young adults. Life stages already defined by identity exploration have been complicated by the pressure to curate and perform a certain self-image online, where external validation and social comparison thrive (with each “like” acting almost like a microdose of an opioid—producing a fleeting rush and reinforcing dopamine-driven reward cycles that deepen psychological dependency over time).

Young people today are not only consumers of content, but often performers within an attention economy that rewards visibility and extremity. The rise of YouTube Shorts has further intensified this dynamic, promoting rapid, bite-sized consumption that fragments attention spans and fosters a constant low-grade sense of restlessness and anxiety. Over time, this environment may erode young people’s ability to sustain focus, regulate emotions, and develop a stable sense of self. It may also encourage a preference for processing the world through immediate images rather than through symbolic systems like language, potentially weakening capacities for complex verbal reasoning, critical dialogue, and nuanced understanding of others.

Moreover, while YouTube has democratized knowledge and empowered many positive movements, its vast scale and algorithmic design raise important concerns. Left unexamined, its capacity to normalize unattainable ideals, reinforce echo chambers—environments where individuals are primarily exposed to ideas that mirror their own, fostering a psychological safety rooted in sameness, but diminishing opportunities to encounter and understand others—and subtly shape worldviews could have lasting effects on how young people see themselves and relate to others. As YouTube continues to evolve, it will be critical for society—including educators, parents, and the platform itself—to remain mindful of its psychological impact and to cultivate healthier, more expansive ways of engaging with it.

Sheeran, Bieber, and T Swift alongside hobbyists and influencers
Harvey Young, dean, College of Fine Arts

YouTube has indisputably been a game changer. Today’s culture of social media influencers and DIY hobbyists—as well as the rise of TikTok and Instagram “Reels”—are all the result of YouTube. 

YouTube gave emerging artists a platform to introduce themselves and allowed established artists an opportunity to get paid when people stream their videos. A generation ago, people patiently waited for MTV’s Total Request Live or one of VH1’s video countdowns and even earlier would tune in to Casey Kasem and Rick Dees on the radio with the hope of hearing a certain song. Today, it’s all on demand and immediate. With the change, people in large numbers abandoned those traditional platforms. 

When you think about it, a group like Blackpink, with 96 million subscribers, or an artist like Taylor Swift, with nearly 61 million subscribers, have been able to create an impact that rivals the Beatles through their YouTube presence—despite the proliferation of television and social media channels competing for our attention. YouTube uniquely functions as a common ground—the basis for water cooler conversations thanks to algorithms that push content our way—as well as a place where we can discover the newest songwriter who just uploaded their first recording. That’s pretty amazing when you think about it.

With more than two billion users worldwide, the impact of YouTube on culture is undeniable. Overall, it’s been a good thing. There are plenty of downsides, especially user addiction to the relentless flow of content. Sprout Social recently noted that people spend more time on YouTube than any other social media service.

But what is exciting about YouTube is that it still exists as a space where an artist can be discovered. Ed Sheeran famously used the platform to fan the flames of his growing popularity. And a decade ago, Teen Vogue pointed to Justin Bieber and Carly Rae Jepsen as folks whose YouTube presence led to record contracts. 

Risks, benefits for our mental health
Hyeouk “Chris” Hahm, professor and associate dean for research, School of Social Work

I think YouTube has become an enormous hub for mental health information. It is now more widely used by people seeking health and mental health information than many traditional healthcare websites.

However, this accessibility also comes with significant risks. The information shared on YouTube can shape people’s health beliefs, behaviors, and coping strategies—but not always in ways that are accurate or evidence-based.

For example, one study analyzing depression-related content on YouTube found that only 9 percent of videos were uploaded by mental health professionals or organizations, whereas 36 percent were uploaded by influential vloggers, many of whom have thousands to millions of subscribers. Often, people are drawn more to information that is compelling and emotionally stirring than to peer-reviewed research.

This means that patients—and sometimes even providers—are increasingly and simultaneously exposed to competing narratives, including personal anecdotes, sensational stories, as well as the scientific advice. While YouTube has encouraged more open conversations about mental health, it has also made it easier for misinformation to spread.