Trying to figure out what is banned and what is not has taken on new urgency in the aftermath of Google's withdrawal from China over censorship concerns and the strong stance of the Obama administration on Internet freedom.
In China, each website basically censors itself, so though there are universal taboos — anything about Tibetan independence, for example — you are never quite sure when, shall we say, one of the seven words will hit the fan. Some words can be searched in English, but not in Chinese, or vice versa. What's sensitive one day might be legit the next.
...The Chinese government doesn't even call it censorship, the preferred term being "guidance of public opinion." Chinese Internet users often say that a website has been "harmonized," a waggish reference to Communist Party slogans about building "harmonious society."
You don't always know when you're being censored — sorry, guided. When searching a sensitive subject, you will be frustrated with a blank screen and a vague error message ("the connection to the server was reset while the page was loading" is the most common) so that you're never quite sure if you've hit the wall or if some technical glitch really did cause the problem.