Imperial academy is an ancient national university in China. It was founded in the Western Zhou Dynasty and went through the Spring and Autumn Period, the Warring States Period, the Wei, Jin, Southern and Northern Dynasties, until the end of the Qing Dynasty. Imperial academy was a central official school, and it was the highest institution for poor Confucian scholars to pursue further studies at that time. The purpose of education in imperial academy is to cultivate a scholar who is "loyal and loves the past" and become the highest performer of applying classics. Imperial academy takes Confucian classics as the main teaching content and the Five Classics as the main teaching material. Imperial College's examination system is very strict, with grades, which are divided into upper, middle and lower grades according to students' usual conduct and academic performance. Those with excellent grades will be appreciated and reused by the emperor; Those who fail will be listed below and deleted from the list.