East Asian languages, especially Chinese, Japanese, Korean and Vietnamese, all share a common characteristic: The writing systems all completely or partly use Chinese characters — Hànzì in Chinese, kanji in Japanese, hanja in Korean, and Hán tự in Vietnamese.
Chinese is written in Chinese characters only and requires approximately 4,000 characters for general literacy although there are up to 40,000 characters for reasonably complete coverage.
Japanese uses fewer characters — general literacy in Japan can be expected with about 2,000 characters — together with two syllabaries (hiragana and katakana).
The use of Chinese characters in Korea is becoming increasingly rare. Hangul is now the native writing system of Korean.
In the past, Vietnamese used Han-Nôm prior to adopting Quốc Ngữ. The written form of Han-Nôm died out during the 20th century.