Internet censorship in the People's Republic of China (PRC) affects both publishing and viewing online material. Many controversial events are censored from news coverage, preventing many Chinese citizens from knowing about the actions of their government, and severely restricting freedom of the press. Such measures, including the complete blockage of various websites, inspired the policy's nickname, the "Great Firewall of China", which blocks websites. Methods used to block websites and pages include DNS spoofing, blocking access to IP addresses, analyzing and filtering URLs, packet inspection, and resetting connections.
China's Internet censorship is more comprehensive and sophisticated than any other country in the world. The government blocks website content and monitors Internet access. As required by the government, major Internet platforms in China established elaborate self-censorship mechanisms. As of 2019 more than sixty online restrictions had been created by the Government of China and implemented by provincial branches of state-owned ISPs, companies and organizations. Some companies hire teams and invested in powerful artificial intelligence algorithms to police and remove illegal online content.
Amnesty International states that China has "the largest recorded number of imprisoned journalists and cyber-dissidents in the world" and Reporters Without Borders stated in 2010 and 2012 that "China is the world's biggest prison for netizens."
About 904 million people have access to Internet in China. Commonly alleged user offenses include communicating with organized groups abroad, signing controversial online petitions, and forcibly calling for government reform. The government has escalated its efforts to reduce coverage and commentary that is critical of the regime after a series of large anti-pollution and anti-corruption protests, and in region of Xinjiang and Tibet which are subjected to terrorism. Many of these protests as well as ethnic riots were organized or publicized using instant messaging services, chat rooms, and text messages. China's Internet police force was reported by official state media to be 2 million strong in 2013.
China's special administrative regions of Hong Kong and Macau are outside the Great Firewall. However, it was reported that the central government authorities have been closely monitoring Internet use in these regions
