News from Loyola University Chicago Libraries.
This guide is to assist researchers looking for information on specific Chicago communities.
For the purposes of this guide, these are how the terms are defined
Block groups - consist of several blocks; there are typically between three and five block groups to a tract.
Community - a geographic area as defined in the 1920's as one of the 77Chicago areas created so the census bureau and social scientists could track statistics consistently in defined areas over time.
Congressional districts - a (physical) division of a state which is entitled to elect one member to the United States House of Representatives to represent their interests.
Neighborhood - a geographic area where it's boundries are reevaluated after each federal census and its boundaries may change over time.
Tract - a geographic region defined for the purpose of taking a census. Usually these coincide with the limits of cities, towns or other administrative areas and several tracts commonly exist within a county. They have changed a great deal over the years, in most cases by splitting.
Ward - one of the City of Chicago's 50 legislative districts (also called political districts). Each ward has one elected alderman. Together they form a Council, which, with the mayor, govern the city. Ward boundaries must be re-drawn after every federal census.