History of education
Although there are more than 40,000 Chinese characters in written Chinese, many are rarely used. Studies have shown that full literacy in the Chinese language requires a knowledge of only between three and four thousand characters.
Chinese characters
Despite standardization, some nonstandard forms are commonly used, especially in handwriting. In older sources, even authoritative ones, variant characters are commonplace. For example, in the preface to the "Imperial Dictionary", there are 30 variant characters which are not found in the dictionary itself. A few of these are reproduced at right.