China has the world's largest number of internet users, around 829 million according to the government - that is twice the population of the United States.
It also has one of the most restrictive internet environments in the world.
The regulations and censorship have not stopped Chinese citizens from embracing the internet, but the rules governing what is and is not permitted on the internet in China is constantly changing and is not always clear.
Al Jazeera's Katrina Yu explains how China has implemented the world’s most advanced system of internet controls.
