It was the tweet that broke the Internet, at least figuratively. No, we are not talking about Kim Kardashian.
The so-called "Golden Tweet" of 2014 came from Ellen DeGeneres, whose star-studded selfie at the Oscars was re-tweeted more than 3.3 million times.
Twitter (TWTR) on Wednesday released its annual list of the events and personalities that attracted the most attention on the social network where people circulate more than 500 million messages, photos and links every day.
Users have taken social activism to Twitter, while mega sports and news events were also big drivers.
Recently, the hashtag #ICantBreathe has emerged in the days since a grand jury on Staten Island declined to indict a white officer in case of Eric Garner, an unarmed man who died after the officer used a choke hold to subdue him. His last words were "I can't breathe."
Outrage over police brutality and racism following the New York incident and another in Ferguson, Missouri, gave rise to the hashtag #BlackLivesMatter.
The Michael Brown case spawned more than 18 million tweets with the hashtag #Ferguson as protests flared there in August.
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The pro-Democracy movement in Hong Kong has been another a popular Twitter topic. There were more than 2.3 million tweets about the #UmbrellaRevolution, as the protests are known.
One of the biggest Twitter "moments" of 2014 was the World Cup. When Germany won the Cup, soccer fans unleashed a flurry of 618,725 tweets per minute, the biggest traffic peak of the year. Overall, there were 672 million tweets sent by fans, players and teams during the month-long soccer tournament in Brazil.
The Winter Olympics in Sochi and the Super Bowl were also big on Twitter.
Many people took to Twitter to express outrage on international issues -- millions of tweets with the phrase #BringBackOurGirls were sent around the world in a two-week period after more than 200 girls were kidnapped in Nigeria by the terrorist group Boko Haram.
And others expressed their support or lack of for other causes. Scotland's referendum on independence from the United Kingdom sparked the hashtag #IndyRef and was tweeted more than 3.7 million times throughout the campaign. The Scots ultimately voted against independence.
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While many Hollywood or pop stars are wildly popular and have millions of followers, some individuals featured prominently on Twitter this year for other reasons.
Malala Yousafzai, the Pakastani activist and 2014 Nobel Prize winner, and actor Emma Watson, who launched the #HeForShe movement for gender equality, were standout topics. And #RipRobinWilliams was a top trend in August after the comedian took his own life.
Meanwhile, Kardashian's nude photo shoot for Paper magazine didn't quite #breaktheinternet. However, it spawned a host of memes and parodies that kept Twitter users entertained for a few days.
