Old Chinese, or Archaic Chinese (Simplified Chinese上古汉语, Traditional Chinese上古漢語), refers to the Chinese spoken during the Zhou Dynasty (10th century BC - 256 BC). The term is usually used in Historical Chinese phonology, which tries to reconstruct the way in which Old Chinese was pronounced.
Since Old Chinese was the language spoken by Chinese when classical works such as the Analects of Confucius, the Mencius, the Tao Te Ching, etc. were written, Old Chinese was preserved for the next two millennia in the form of Classical Chinese, a style of written Chinese that emulates the grammar and vocabulary of Old Chinese as presented in those works. Classical Chinese was for two millennia the usual language used for official purposes in China, Korea, Japan, and Vietnam.
The phonology of Old Chinese was not preserved in Classical Chinese, however, because the Chinese writing system does not specifically show pronunciation. As a result, the pronunciation of Old Chinese can only be very tentatively reconstructed, and is unknown outside academic circles.
Phonology
For the pronunciation of Classical Chinese, see Classical Chinese#Pronunciation
There is much dispute over the precise way in which Old Chinese was pronounced. It is, however, generally agreed that Old Chinese had consonant clusters such as kl- and pl-, which do not occur in any modern Chinese dialect. Moreover, many modern linguists specializing in historical Chinese phonology contend that Old Chinese was not a tonal language: the tones of Middle Chinese and modern spoken Chinese evolved from consonant clusters that have since disappeared.
Grammar
See Classical Chinese#Grammar
