How does your city define its neighborhoods/districts?

[Docere]

I think the 59 community districts are the main local unit for statistical collection.

I guess Manhattan can be characterized as having larger districts and smaller subsections/neighborhoods within: Carnegie Hill and Yorkville within the Upper East Side, East Village and Bowery within the Lower East Side etc.

This Wikipedia map is quite detailed, so it picks up very niche commercial areas like the Diamond District as well.