Chinese characters are logograms used in the writing of Chinese (in which case they may be called hanzi;汉字/漢字 "Han character") and Japanese (kanji). Such characters are also used, albeit less frequently, in Korean (hanja), and were formerly used in Vietnamese (hán tự), as well as a number of other languages. Chinese characters constitute the oldest continuously used system of writing in the world.

Chinese characters number in the tens of thousands, though most of these are minor graphic variants only encountered in historical texts. Studies carried out in China have shown that functional literacy requires a knowledge of between three and four thousand characters.

In Chinese orthography, the characters are largely morphosyllabic, each corresponding to a spoken syllable with a distinct meaning. However, the majority of Chinese words today consist of two or more characters. About 10% of native words have two syllables without separate meanings, but they are nonetheless written with two characters. Some characters, generally ligatures, represent polysyllabic words or even phrases, though this is the exception and is generally informal.