China’s Great Firewall, a massive system of Internet filters and blocking, has long had a crack in it. The firewall prevents most users inside China from accessing platforms outside the country, such as Facebook, Google and Netflix, in keeping with China’s desire to censor what can be seen and read. But popular software known as virtual private networks, or VPNs, permit a user inside China to tunnel through the firewall. Now the crack is being gradually cemented up.

A VPN has been particularly useful for foreign firms that come to China and want to link up with corporate networks outside it. Hoping to encourage such investment, China looked the other way for years at the existence of the VPNs, many available from Apple’s App Store in China. Some were easy to use — just tap the button and a user would be on Facebook as if sitting in Los Angeles instead of Beijing. The VPNs are popular among millions of young people, as well as journalists and others.
https://www.washingtonpost.com/opinions/china-and-russia-go-further-in-squelching-internet-freedom/2017/08/09/6d10608a-7638-11e7-8839-ec48ec4cae25_story.html