It is the symbol for the birth of publication that books have been distributed to the public.Chinese publication emerged at the Han dynasty.Before the Han dynasty books were not be allowed to be distributed to the public because they all belonged to the government.This situation had been changed since Zhan Guo Period.At the early Han Dynasty

the government abolished the office book policy.At he late Xi Han

proofread the books by Liu Xiang successfully

books have been distributed to the public.According to the period characteristic of publishing development

Chinese publishing history can be divided into four periods:first

before Han Dynasty;second

script period from Han to Tang Dynasty;third

printing period from Wu Dai to late Qing Dynasty;fourth

modern publishing period from late Qing to today.