Censussubdivision (CSD) is the general term for municipalities (as determined by provincial legislation) or areas treated as municipal equivalents for statistical purposes (for example, Indian reserves, Indian settlements and unorganized territories).
Two exceptions are "Subdivision of Unorganized" in Newfoundland and Labrador, and "Subdivision of County Municipality" in Nova Scotia, which are geographic areas created as equivalents for municipalities by Statistics Canada, in cooperation with those provinces, for the purpose of disseminating statistical data.
On-reserve population is a derived census variable that is captured by using the CSD type according to criteria established by Indian and Northern Affairs Canada (INAC).
Generally the smaller, more urban censussubdivisions (towns, villages, etc.) are combined with the surrounding, larger, more rural censussubdivision, in order to create a geographic level between the censussubdivision and the census division.
Censussubdivisions having a land area smaller than 25 square kilometres are usually grouped with a larger censussubdivision.
A censussubdivision with a land area greater than 25 square kilometres and surrounded on more than half its perimeter by another censussubdivision is usually included as part of the CCS formed by the surrounding censussubdivision.