China employs what is known as the Great Firewall of China, or the Golden Shield Project, to monitor and sometimes block internet access to sites within and from beyond China’s borders. Days ahead of the the 20th anniversary of the Tiananmen Square democracy movement, the Chinese government has detained a prominent dissident, disrupted satellite news broadcasts and blocked access to popular web sites inuding: Bing, Live.com, Hotmail.com, Flickr.com and Twitter.com. The video-sharing site YouTube has been blocked in China since March.

Source:→ The New York Times