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.
CKC Chinese Input System
The encoding uses a maximum of 4 digits ("0" - "9") to represent a Chinese character. All possible shapes of strokes that forms any given Chinese character are classified into 10 groups, each represented by one of the ten possible digits 0-9. Chinese characters can then be input by following the order in which the strokes are identified at the 4 corners of the character. As a result of this simplicity in coding using the ten numeric digits, users typically need to use only a numeric keypad to input Chinese.