Age means nothing when it comes to technology and innovation, as demonstrated by the entrepreneurs behind the biggest social media companies.

Meet the young and brilliant social media visionaries who changed the way the world communicates and brought new meaning to “being connected.”

1. Facebook: Mark Zuckerberg

If you’ve seen The Social Network, you know the story of Zuckerberg designing “the facebook” as a sophomore from his dorm room to connect Harvard college students. Facebook’s billion plus users have catapulted Mark Zuckerberg to worldwide fame and grown his personal net worth to $35.7 billion as of 2015.

2. Twitter: Evan Williams, Jack Dorsey and Biz Stone

Dorsey came up with Twitter while in college at NYU during a brainstorming session for the podcast company Odeo. The code name for the service was “twttr,”inspired by Flickr and the five-character length of American SMS short codes. In 2015, Twitter was worth $19 billion.

3. Instagram: Kevin Systrom and Mike Krieger

Created by Systrom and Krieger in 2010, Instagram is a relatively new social media platform. It allows users to take photos and short videos, apply filters, and then share them on various social networking sites. Systrom and Krieger sold this simple, yet profitable idea to Facebook in April 2012 for $1 billion in cash and stock.

4. Pinterest: Paul Sciarra, Evan Sharp, and Ben Silbermann

Pinterest wasn’t an instant success. When Sciarra, Sharp, and Silbermann began developing Pinterest in 2009, Silbermann personally wrote to the site’s first 5,000 users offering his personal phone number and even meeting with some users. Nine months after launch the website had only 10,000 users, and the founders were operating out of a small apartment. However, the launch of an iPhone app in March 2011 brought in more than the expected number of downloads. That August, Time magazine listed Pinterest as one of the “50 Best Websites of 2011,” and by December 2011 the site was one of the top 10 largest social network services.

5. Snapchat: Bobby Murphy and Evan Spiegel

Snapchat, the newest of these social media tools, was also designed by young geniuses. A product design major at Stanford University, Evan Speigel, with the help of his friend Murphy, started Snapchat as a project for one of Spiegel’s classes. When Spiegel presented the idea to his product design class, classmates didn’t like the idea of the disappearing photos. Despite their feedback, Spiegel launched Snapchat in September 2011 in his father’s living room. On November 15, 2013, Google offered $4 billion for the company, but Evan Spiegel declined. You can bet those classmates are eating their words now, as the company was valued at $16 billion in March of 2016.

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