Not to be paranoid, but you are being watched, sort of.
Inside the People's Republic of China, whether you bring your own computer or smartphone, use a computer provided by the hotel, or go to a local “internet cafe” (called wang ba 网吧 ), all your browsing, uploading, and email have to pass through one government-controlled gateway. Expatriates and business travelers call this central server the “Great Fire Wall” or GFW, in a poetic allusion to the physical Great Wall’s job to control access to the frontier.
Beijing uses the GFW in several ways. First, it can block access to any specific domain outside China. Second, it can filter all the Internet traffic inside China. That’s a lot of traffic, and they employ thousands of people to watch what is going on.
Regardless of your personal views, this is something that the government claims the right to do to protect its citizens from “dangerous, objectionable, or immoral” material. Western governments do some of this too, especially in the name of fighting terrorism.
Major news sites such as CNN, the New York Times, Huffington Post, the BBC, and Fox are often censored or blocked entirely. Google is banned, as are foreign email services like Gmail and Yahoo!; and social-networking sites like Twitter and Facebook. Your local newspaper, TV station, or less well-known news source may well be unblocked, but content syndicated by prohibited sources will error out. Beijing does realize its citizens need access to the outside world in order to compete economically and socially, but has to juggle that with maintaining ‘the party line’. The service greatfirewallofchina.org is an easy-to-use resource to test if the website you plan to use while inside the PRC will actually be available to you:
Shopping and airline sites are usually unblocked, so you can check in online for your flight home.
In practical terms, you specifically as a Western family traveler are not being watched. But your login and browsing records will be kept under a real-name file (no anonymous users in China...) - depending on the server you try to access, you may even have to supply your passport information.
If you browse around on Chinese-based websites, you’ll see various official-looking or police-themed logos at the bottom of the page, or code that says “ICP number number.” These certify that the website or blog has been registered with the government, as is their law.
Your email goes through the GFW as well, even if you’re not using a Yahoo!, MSN, or Gmail account. It is supposedly screened for keywords to make sure you are not passing along state secrets or inciting unrest, and as such may not be delivered immediately. To be safe, don’t write about the Things You Are Not Supposed To Talk About In China, and you won’t be bothered.