Social networking sites allow people to connect with other people and organizations. They are highly interactive and encourage people to communicate with others. They allow a host of media content (photos, videos, etc.) but are primarily designed around individual social interactions. They are what most people think of first when they think about social media. These platforms can now create content that is more accessible for people with access and functional needs, including photo and video captioning. The most popular platforms in 2021 include:

• Facebook: Founded in 2004 to help college students connect. Now nearly 70% of U.S. adults report using the platform (Pew Research, 2019). Overall, this platform increasingly reaches an older audience. Requires an account to see most content. It has a wide array of open and closed groups focused on specific topics and has the ability for organizations to set up pages that people can follow. Has the ability to live-stream video
• Twitter: Founded in 2006, this platform initially limited posts to 140 characters and was designed to be updated via text message. It has since evolved into a robust multi-media platform used by 22% of U.S. adults, though posts are still limited to 280 characters. Overall, this platform reaches a younger audience than Facebook, though it is widely used by media outlets to share information. It does not require an account to see content, so people may view posts without signing up for the service. Twitter also has the ability to live-stream video.
• LinkedIn: Founded in 2003 and since purchased by Microsoft, is primarily focused on professional networking. It requires users to provide some of their professional background to set up a profile. A wide variety of special interest groups exist on LinkedIn. Organizations can set up pages that users can follow. 27% of U.S. adults report having a LinkedIn account.

Source: Social Media Fact Sheet (https://www.pewresearch.org/internet/fact-sheet/social-media/)