The first is the county system. We often talk about feudalism. What is feudalism? The so-called feudalism is to establish a country by enfeoffment. In the history of China, only Xia, Shang and Zhou dynasties made enfeoffment. After the Qin Dynasty created the county system, it has been used by successive dynasties.
Followed by the emperor's name and self-proclaimed. Before the Qin dynasty, there were no names like the emperor and me. It all started with Qin Shihuang.
Third, unify words and weights and measures. Although this was the system of the Qin dynasty, it was not really fully implemented and popularized until the Han dynasty because of the short time of reunification of the Qin dynasty.
Fourth, the system of three publics and nine ministers. The central organization of the Qin Dynasty was headed by the emperor and implemented the system of "three public officials and nine ministers". The three public officials are the Prime Minister, Qiu and Tai Shigong. This system was also inherited by later generations.
The whole system constitutes a dictatorial centralization. Be inherited by future generations. Most of the systems in the Han Dynasty were developed and perfected on the basis of the Qin system.
Shallow knowledge, lots of advice.