Social media is constantly being discussed thus far in the 2012 Olympics, but what about back in 2008? With only 6 million Twitter users that year, #beijing2008 definitely wasn’t at the bottom of your television screen. A lot has changed in four years: Twitter now caters to 500 million and Facebook has grown by 800 million.  Compare the number of likes on the Olympics pages: Beijing has just over 329,000 while London, as of now, has more than 1.1 million. Social media has skyrocketed since the last summer games and everyone, from athletes to organizations, is taking advantage of it.

Michael Phelps (@MichaelPhelps) only started tweeting last October but has racked up close to 500,000 followers. Per sports business analyst Darren Rovell, in the past 24 hours alone– after Phelps’ collected his 19th Olympic medal– he gained an additional 161,000 followers.  Fans, other Olympians and even the POTUS have all taken to Twitter to congratulate Phelps on his historic achievement.

President Barack Obama congratulated Michael Phelps on his 19th Olympic medal

Phelps tweeted a picture of his 18th and 19th career Olympic medals

But Phelps isn’t the only athlete turning to Twitter to reach out to fans.  Lolo Jones (@lolojones) has made controversial Twitter headlines. Usain Bolt (@usainbolt) avidly tweets pictures and remains one of the most popular athletes on the site. And Ryan Lochte (@ryanlochte) interacts with his followers more than most other Olympians. By using Twitter so wisely, these athletes are simultaneously increasing their fan bases and marketing themselves; all for free. Seven out of the last 10 tweets by Ryan Lochte are retweets: a kind of personal touch can create fans for life.

Lolo Jones is becoming well-known for her witty comments

Usain Bolt does a great job in showing fans a behind-the-scenes look at the life of an Olympian

But Twitter is not the only social media outlet that is benefiting from the games. Foursquare, a social media app that allows you to ‘check in’ to places, is also trying to profit from the Olympic action. The company has been trying to get other companies on board so that users can ‘unlock’ deals if they check into a certain location. Their only roadblock: Foursquare is partnered with American Express, the Olympics are sponsored by Visa. Regardless, the little app that could is proving that it can contend with the top dogs and plans to unlock the city of London for its users.

Since 2008, people have come to rely on social media for much more than a reminder that it’s someone’s birthday. It is a way to connect people from all over the world, same as the Olympics. By combining the two, the 500 million of us on Twitter and 955 million on Facebook never have to miss a beat. Getting to know Usain, Ryan, Lolo, Michael, and almost every Olympic athlete out there is as easy as clicking follow.

Which Olympic athletes do you follow on social media?