CJK characters
Chinese is written almost exclusively in Chinese characters. It requires over 3,000 characters for general literacy, but up to 40,000 characters for reasonably complete coverage. Japanese uses fewer characters — general literacy in Japanese can be expected with 1,945 characters. The use of Chinese characters in Korea is becoming increasingly rare, although idiosyncratic use of Chinese characters in proper names requires knowledge (and therefore availability) of many more characters. However, even today, students in South Korea are taught 1,800 characters.
Chinese language
The most comprehensive pure linguistic Chinese-language dictionary, the 12-volume "Hanyu Da Cidian", records more than 23,000 head Chinese characters and gives over 370,000 definitions. The 1999 revised "Cihai", a multi-volume encyclopedic dictionary reference work, gives 122,836 vocabulary entry definitions under 19,485 Chinese characters, including proper names, phrases and common zoological, geographical, sociological, scientific and technical terms.