A 2002 study by Harvard Law School found that China had the most extensive system of Internet censorship in the world, denying users access to 19,000 websites, including those run by Amnesty International and Human Rights Watch. But in the decade since, the Great Firewall has only grown taller. Sites that were once only temporarily blocked -- Facebook, YouTube, and Twitter -- have been permanently banned since 2008. The government has stepped up efforts to monitor Internet activity, banishing sensitive words from social networking sites, and hiring monitors to "steer" online conversations. At the same time, Internet usage in China has skyrocketed -- there are currently 538 million Internet users in China and counting. And while many use it for recreation, China's online population has become increasingly sophisticated about staying a few steps ahead of the government's censorship tools.
Above, young men play online games at a café in Beijing in February 2010.
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