Digital tools such as YouTube, Twitter and Facebook have defined this year's social movements by giving rise to a new generation of activism. In 2008, Barack Obama's campaign was touted for its social media prowess. 2011's stories of online mobilization share a common thread, differentiating them from the U.S. President's election effort: grassroots organization by average individuals.
As more of the world becomes connected online, revolutionaries across the globe are being empowered like never before.
We took a look at some of the biggest stories of activism and uprising that were organized using social media this year. Take a look through the gallery below to relive some of the year's most memorable moments and examine their digital roots.
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