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Social media

Screenshot of first tweet, from username jack with text "inviting coworkers".
On March 21, 2006, Twitter co-founder Jack Dorsey wrote that as the first tweet. It amassed a huge number of retweets and likes in the years since.
The team behind Twitter originally envisioned the service as a way to share status updates with anyone interested in your updates. You could "follow" other Twitter accounts, but they didn't have to follow you back.
That asymmetry leads to a social graph with multiple types of relationships between users:
Diagram of social graph with one user at the center and arrows to and from 6 other users. Four of the users have an arrow pointing in at the center user, one user has arrows both to and from the center user, and another user has an arrow coming from the center user.
The center user is followed by others, mutually follows one user, and follows another user who doesn't follow them back.
Twitter was asymmetric from the beginning, but once other social networks saw the success of that model, many added on follow-like features. Now you can be a fan on Facebook, follow on Instagram, or subscribe on YouTube.
Montage of screenshots from social media websites: follow button on Pinterest, follow button on Instagram, follow button on a Tumblr blog, subscribe button on a YouTube channel, and follow and like buttons on a Facebook page.
Follow buttons from Pinterest, Tumblr, Facebook, YouTube, Instagram.

Viral spread

Lots of people still use social media primarily as a way to connect with their friends and family, but increasingly, people are using social media as a way to spread and consume information across wider networks.
Information can easily "go viral" on social media, since it's so easy to write a post and even easier to click a button to share a post with your network.
In May 2016, one woman streamed a live video to her Facebook fans where she gleefully unboxed and wore a Chewbacca mask. Within a week, the video had over 100 million views and she was invited to meet the Chewbacca actor himself.
Screen capture from live streamed video, of a woman with a Chewbacca mask. Video overlay says it has 176,950,391 views.
Social media users couldn't resist this happy Chewbacca.
The majority of social network users have a small number of followers, but it only takes a few super-connected users for a post to go viral.
Diagram of a social graph with a super-connector. A single user is followed by three users, the first follower has 2 followers, the second follower has 3 followers, and the third follower has 15 followers.
Super-connected users have big audiences on social media.

News sharing

We don't use social media just for entertainment purposes; in 2018, the majority of Americans read news on social media. In fact, more Americans now get their news from social media than from print newspapers.
Two charts about social media and news. The first is a pie chart labeled "% of US adults who get news on social media", with pie slices of "Never" at 32%, "Hardly ever" at 21%, "Sometimes" at 27% and "Often" at 20%. The second is a line chart labeled "% of US adults who get news often from each source", with an x axis from 2016 to 2018. The line labeled "Television" starts at 57% and ends at 49%. The line labeled "New website" starts at 28% and ends at 33%. The line labeled "Radio" starts at 25% and ends at 26%. The line labeled "Social media" starts at 18% and ends at 20%. The line labeled "Print newspaper" starts at 20% and ends at 16%.
At the same time, 57% of US social media users expect news on social media to be largely inaccurate, and Europeans trust social media less than any other news source.1
Chart of trustworthiness of news sources.
European trust in news sources. Data source: EBU Trust in Media 2017
Some of the news is purposefully inaccurate, and that's been termed fake news. Other news articles may be accidentally inaccurate, based on unreliable sources, especially for breaking events.
Why does inaccurate news spread so easily on social media? Researchers think it's due to information overload; social media users can scroll through hundreds of posts in a short period of time, and there's just too much information for them to reason about. 2

Echo chambers

Researchers are also concerned about echo chambers. On social media, people tend to be connected to people with similar ideologies and thus are more likely to see content that aligns with their beliefs. They're also less likely to apply a rigorous accuracy check to that ideologically aligned content, so they are more apt to share it.
This visualization shows two disparate echo chambers on Twitter during the Brexit debate, an UK referendum which supported UK leaving the EU.
A visualization of thousands of nodes connected to each other, with each node representing a hashtag. Some hashtags are labeled, and the two largest are "bremain" on the left and "brexit" on the right. The nodes are colored red or blue depending on their alignment with either "bremain" or "brexit", and there is little overlap between the red and blue nodes.
Visualization of 13,310 co-occurring hashtags on Instagram related to the UK's EU referendum debate. Each hashtag is colored according to its alignment with either remaining in or leaving the EU, and the hashtags are positioned near overlapping hashtags. Read more details here. Image source: Vyacheslav Polonski
Social media has the potential to enable the free flowing of ideas between many different people, but yet the ideas don't seem to be flowing between groups with opposing beliefs. If we stay within our echo chambers on social media, we may never get the chance to understand other perspectives and have our own beliefs challenged.

Social media privacy

Social media networks vary in their privacy settings. Some networks default to sharing posts with friends and others default to sharing posts publicly (viewable by anyone on the Internet).
Here's part of the privacy policy from Instagram, a photo-sharing network:
"Any information or content that you voluntarily disclose for posting to the Service, such as User Content, becomes available to the public, as controlled by any applicable privacy settings that you set. To change your privacy settings on the Service, please change your profile setting. Once you have shared User Content or made it public, that User Content may be re-shared by others." 3
That policy is written in legalese, which can be a bit hard to follow. Put simply, Instagram defaults to public posts but gives users options.
In the Instagram settings, users can choose to share posts more privately:
Screenshot of the Instagram privacy settings. Includes an unchecked checkbox next to "Private Account" which says "When your account is private, only people you approve can see your photos and videos on Instagram. Your existing followers won't be affected."
How many users that sign up for a social media network are aware of who can see their posts—and aware of their options for changing that?
A 2019 survey asked people "How often do you click to accept a company’s privacy policy without reading it?" The results:
Screenshot of a chart divided by age group, with bars for "Never", "Sometimes", "Usually", and "Always". The bars for "Usually" and "Always" tend to be bigger than "Never" and "Sometimes" across the age groups.
Chart source: Axios
The majority of people (56%) said they always or usually skip reading the policy before accepting it, with younger generations more likely to skip than older. 4

Risks of public posts

A publicly viewable post is a great way to share news, viewpoints, or just sheer joy with a wide audience. There are some definite risks, however:
Cybercrime: An attacker can use PII revealed in public posts to help them steal the identity of a social media user or hack into their accounts. They could also use geolocation information from public posts to physically stalk an individual.
Reputation damage: A social media user who has a public reputation can build up their reputation on social media, but they can just as easily ruin their reputation from a badly worded post. The social media world is often quick to pass judgment. For that reason, celebrities and companies may choose to work with brand agents to carefully craft their social media persona.
Job loss: Social media users have been known to lose their job over the contents of their posts, like posts that are disparaging about the company or offensive to many people. There are also likely many users that have lost the chance at a future job after a potential employers looks at their posts and doesn't like what they see.

Difficulty of deletion

If you're a social media user, you might be reading this and starting to wonder if maybe this is a good time to clean up your social media accounts: delete a few personal photos, remove some opinions you no longer hold, that sort of thing.
The good news: social media networks pretty much always give users an options to delete their posts or their entire account. That should delete the data from the network's servers and from being viewed directly on your profile page.
The bad news: once anything has been published online, it can be very difficult or impossible to delete. That's because of the many copies that might exist, due to mechanisms such as:
Web archiving services: The Internet archive is a non-profit that attempts to make copies of all the pages on the Web, and anyone can use their WaybackMachine to browse their archives.
Here's a snapshot taken by the Internet Archive of my personal homepage from way back in 1998 (when I was in eighth grade):
Screenshot from the Internet Archive Wayback Machine for Jan 17, 1998. Website includes text about favorite TV shows and favorite movies.
URL has been blurred to protect the innocent.
Automated bots: Search engines may copy pages they find online and keep a cached version, even if the page itself goes offline.
Other users: When another user sees a post they like, they could use the network's built-in mechanism for sharing it (such as retweeting on Twitter or regramming on Instagram). But they could also take a screenshot of a post or download a photo, and share it on that network, other networks, or even a news article.
🤔 What other harmful effects can social media have? What benefits do you personally derive from social media? What are ways that people can use social media responsibly?

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