Han tu

Han tu is the term for Chinese characters, which was used to write classical Chinese, in contrast to ''ch? N?m'', which was used to write the Vietnamese language. In imperial Vietnam, formal writings were, in most cases, done in classical Chinese, while Vietnamese was only used for recording literature. These writings are indistinguishable from those classical Chinese works produced in China, Korea, or Japan. The readings of ''Hán t?'', like Kanji and Hanja, reflect that of Middle Chinese, and provide valuable data for the study of historical Chinese phonology. The use of classical Chinese, and its written form, ''Hán t?'', died out in Vietnam during the 20th century, after the and . A system of modified and invented characters modeled loosely on Chinese characters called ''ch? N?m'', which, unlike the system of ''Hán t?'', allowed for the expression of purely Vietnamese words, was created in Vietnam at least as early as the 13th century. While designed for native Vietnamese speakers, it required the user to already know Chinese characters, and thus ''ch? N?m'' was used primarily for literary writings by cultural elites , while all other official writings and documents continued to be written in ''Hán t?'' until the 20th century.