Arif asked about hierarchies of government. Take India:

1 county
2 state
3 division
4 district
5 subdivision
6 police station
7 union
8 village

That's 8!
And they all nest: n units of order x nest inside a unit of order x-1.

country, state, district and police station are the most important, and show up on most maps. Unions and especially villages are the basic units for census and basic admin. Each village has a local council, and in the old days had a chaukidar, or watchman, village headman, etc.
These 8 levels of government are more than just ward or electoarate boundaries for electoral purposes. Levels 3 to 6 have their officials appointed. Only levels 1,2 and 7 and 8 have elected officials.

Census unit areas in Australia and NZ are no more than small areas for convenience of counting. but the village is the basic unit of government and admin in India. Bangladesh is similar, and has at least 6 levels
country,
division,
*superdistricts (the old districts, not sure if they mean much now),
districts/zilas (the old subdivisions, elevated to districts in the 1980s)
thanas/police stations
unions
*mauzas
villages.

In many cases there is only 1 village per mauza, so these are equivalent.
Eg
country: bangladesh
division: Rajshahi
(superdistrict: old Rangpur district)
district: Lalmonirhat
thana: Patgram
Union: Dahagram
(mauza: Angarpota)
Village: Angarpota

In this case, Dahagram Union is made up of 2 mauza: Dahagram and Angarpota, which together form the largest Bangladeshi enclave in India.

Brendan