Historical Records is a biography of China. It took Sima Qian 18 years to write it. Encyclopedia 130 volume, 520,000 words, including biographies 12, tables 10, 8 books, 30 families, 70 biographies, a total of about 526,500 words, recording the period from the legendary Huangdi era in ancient China (about 3000 BC) to the first year of Emperor Wu (BC It is all-encompassing, comprehensive and clear. It records the development of ancient politics, economy, military and culture in detail.