So, for example, in Ukrane there are 24 regions. Every region has its capital city. For example, Im living in Kharkiv, but in Kharkiv`s region there are few cities and countysides, that are not that big. Its more than 1,5 million citizens in Kharkiv, but about 2 millions in Kharkiv`s region. District is like a region but in the city. Kharkiv is separated on 9 districts, each having its own control center. This type of policy is spread only on post soviet space (suck countries as Ukraine, Russian, Belarus). Anyway, hope it was useful for you)