Written Chinese
Because the majority of modern Chinese words contain more than one character, there are at least two measuring sticks for Chinese literacy: the number of characters known, and the number of words known. John DeFrancis, in the introduction to his "Advanced Chinese Reader", estimates that a typical Chinese college graduate recognizes 4,000 to 5,000 characters, and 40,000 to 60,000 words. Jerry Norman, in "Chinese", places the number of characters somewhat lower, at 3,000 to 4,000. These counts are complicated by the tangled development of Chinese characters. In many cases, a single character came to be written in multiple ways. This development was restrained to an extent by the standardization of the seal script during the Qin dynasty, but soon started again. Although the "Shuowen Jiezi" lists 10,516 characters—9,353 of them unique (some of which may already have been out of use by the time it was compiled) plus 1,163 graphic variants—the "Jiyun" of the Northern Song Dynasty, compiled less than a thousand years later in 1039, contains 53,525 characters, most of them graphic variants.
Naming laws in the People's Republic of China
There are over 70,000 known Chinese characters, yet approximately only 32,232 are supported for computer input, including both Traditional and Simplified characters (see GBK (character encoding) etc.). As the government database of personal names is maintained digitally on government networks, input of rarer characters becomes virtually impossible, thus creating an irremovable restriction on permitted names. All citizens within the People's Republic of China must have their details registered on the government computer network, while those over the age of 16 must carry an identification card, known in China as a Resident Identity Card at all times. As these processes are all done electronically, having a name which is not supported by electronic input makes government registration and the management of ID cards much more difficult.