The county system is a means of centralization, and administrative personnel at all levels are appointed by the central government, not decided by local prisoners. Different times have different names, which are roughly divided into three or four levels, namely, Dao, Zhou, County, County or Dao, Zhou, Fu, County or Province, Fu and County. South Korea still uses the administrative divisions of Dao, such as gangwon and Dao. Now China is a province, a city and a county (district). So you see, some rules formulated by Qin Shihuang are still in use today. Including books with the same language and cars with the same track, are all unified means, just like our current education and Putonghua, in order to better unify the nation and unite. In fact, it is to unify the means.