The title of master originated in the Five Dynasties, and it also refers to a person with noble moral character and profound knowledge, but it was never an official position. The ancients said that a master is great. In ancient times, those who were learned were often called "masters of old age" and "masters of Confucianism", meaning similar to masters. China's national education sequence is divided into basic education and higher education. Basic education is the basic education of the people, including preschool education, primary education, junior high school education and senior high school education. Higher education is the education to cultivate high-level talents in society, including junior college, undergraduate and postgraduate education. Postgraduates are divided into two levels: master's degree and doctoral degree. Postgraduates are academic degrees, and bachelors, masters and doctors are degrees. Postdoctoral students are not degrees, but doctoral degree recipients who are allowed to enter Post-Doctoral Research Center for scientific research. It can also be said that postdoctoral represents a kind of work experience. Therefore, what we call "graduate students" refers to graduate students and doctoral students. For undergraduates, the reference to "graduate students" usually refers to master students. The graduate students mentioned in this manual also refer to master students. In Chinese mainland, ordinary people generally call master graduates "graduate students" and doctoral graduates "doctors". Therefore, according to the common name, it has become the ladder of "college students"-"graduate students"-"doctors".