APHG

African city model

A city model showing a mix of traditional, colonial, and modern economic zones, often with a CBD, market zone, and informal settlements.

anti-displacement activists

Individuals who work to prevent residents from being forced out of neighborhoods due to rising housing costs or redevelopment.

automobile cities

Cities designed primarily around car transportation with highways, parking lots, and low-density development.

below market rate housing

Housing priced below typical market value to make it affordable for lower-income residents.

bid-rent theory

A theory explaining how land users compete for central locations, causing land prices to decrease with distance from the city center.

blockbusting

A discriminatory real estate practice where agents scare white homeowners into selling cheaply by suggesting minorities are moving in.

boomburb/boomburg

A rapidly growing suburban city with a population over 100,000.

Borchert’s Epochs

Five periods of U.S. urban growth based on dominant transportation systems.

brownfields

Abandoned or contaminated industrial sites available for redevelopment.

built environment

Human-made surroundings such as buildings, roads, and infrastructure.

Burgess concentric-zone model

A city model showing urban land use in rings expanding outward from a central business district.

census data

Population and housing information collected by the government.

central place

A settlement that provides goods and services to surrounding areas.

Christaller's central place theory

A theory explaining how cities are spaced based on efficient delivery of goods and services.

conurbation

A region where multiple cities have grown together to form one continuous urban area.

decentralize

The movement of people and businesses away from the central city to surrounding areas.

de facto segregation

Segregation that occurs through social or economic conditions rather than laws.

density gradient

The change in population density as distance from the city center increases.

disamenity zone

An area with undesirable features such as pollution or heavy industry.

ecological footprint

The amount of land needed to support a person’s lifestyle.

edge city

A large suburban business district located near highways outside the traditional downtown.

environmental injustice

The unequal exposure of certain groups to environmental hazards.

environmental racism

Environmental policies or practices that disproportionately harm minority communities.

exclusionary zoning

Land-use policies that prevent certain groups from living in an area, often through large lot requirements or housing restrictions.

exurb

A community beyond the suburbs that is economically connected to a city.

favela

A self-built informal settlement commonly found in Brazil.

farmland protection policy

Laws designed to preserve agricultural land from urban development.

field study

Research conducted through direct observation and data collection in real-world settings.

forward capital

Investment used to redevelop or improve an area.

galactic / peripheral city model

A city model featuring a CBD surrounded by edge cities connected by highways.

gated community

A residential area with restricted access and private security.

gentrification

The process of wealthier residents moving into a neighborhood, increasing property values and often displacing lower-income residents.

geographic fragmentation of government

The division of a metropolitan area into many separate municipalities with different governments.

globalization

The increasing interconnectedness of economies, cultures, and populations worldwide.

gravity model

A model predicting interaction between places based on population size and distance.

greenbelt

A protected ring of open land around a city to limit urban sprawl.

Griffin-Ford model

A model of Latin American cities showing a CBD, elite residential sector, and peripheral squatter settlements.

Harris and Ullman multiple nuclei model

A city model with multiple centers of activity rather than one central business district.

historical/place character

The unique cultural and architectural identity of a place shaped by its history.

Hoyt sector model

A city model where development occurs in wedges or sectors extending from the CBD.

housing choice voucher program

A government program that helps low-income families pay rent in the private housing market.

housing discrimination

The unfair treatment of people in housing based on race, income, or other characteristics.

inclusionary zoning (IZ)

Policies requiring developers to include affordable housing in new projects.

infilling/infill

Developing vacant land within an existing urban area.

Latin American city model

A city model featuring a CBD, elite sector, commercial spine, and peripheral squatter settlements.

local food movements

Efforts to promote locally grown and produced food.

megalopolis

A chain of connected metropolitan areas forming a large urban region.

metropolitan statistical area

A region consisting of a core city and its economically connected surrounding counties.

metacities

Cities with populations over 20 million.

metropolis

A major city that serves as a cultural and economic center.

micropolitan statistical area

An urban area centered around a town of 10,000–50,000 people.

mixed land use

Development that combines residential, commercial, and other uses in one area.

mortgage

A loan used to purchase property.

multiple-nuclei model

A city model with several distinct centers of business and residential activity.

NIMBYs (Not In My Backyard)

Residents who oppose developments near their homes.

New Urbanism

A planning movement promoting walkable neighborhoods and mixed land use.

phytoremediation

The use of plants to remove toxins from soil.

primate city

A country’s largest city that is more than twice the size of the next largest city.

public housing

Government-owned housing provided for low-income residents.

quantitative data

Numerical data used for statistical analysis.

qualitative data

Descriptive, non-numerical data.

rank-size rule

A rule stating that a city’s population is inversely proportional to its rank in the urban hierarchy.

redlining

A discriminatory practice denying loans or services to residents of certain areas based on race.

redevelopment

The process of improving or rebuilding urban areas.

remediation

The cleanup of contaminated land.

scattered developments

Low-density housing built far apart without planning.

site

The physical characteristics of a location.

situation

The relative location of a place in relation to other places.

smart growth

Urban planning that promotes sustainable, compact development.

slow-growth cities

Cities that limit development to control expansion.

Southeast Asian city model

A city model showing a mix of colonial influence, port zones, and modern development.

sprawl

Uncontrolled expansion of urban areas into rural land.

squatter settlements

Informal housing built without legal rights to the land.

streetcar suburb

A residential area that developed along streetcar lines.

suburb

A residential area outside the central city.

suburbanization

The movement of people from cities to suburbs.

sustainable design initiatives

Building and planning strategies that reduce environmental impact.

survey data

Information collected from questionnaires or interviews.

threshold

The minimum population needed to support a service.

transportation-oriented development

Development focused around public transit stations.

urban decentralization

The movement of people and businesses from city centers to outskirts.

urban footprint

The physical extent of a city’s built-up area.

urban growth boundary

A legal boundary limiting urban expansion.

urban heat island

The warming of cities compared to surrounding rural areas due to human activity.

urban hierarchy

The ranking of cities based on size and economic importance.

urban renewal

Government programs aimed at revitalizing declining urban areas.

urban sprawl

The spread of low-density development over large areas.

urban sustainability

Planning that balances environmental, economic, and social needs.

urban system

A network of interacting cities.

urban walkability

How friendly an area is to walking.

urbanization rate

The percentage growth of a city’s population over time.

white flight

The movement of white residents from urban areas to suburbs.

world city

A city that is a major center of global economic activity.

zone of abandonment

An area in decline due to economic downturn and disinvestment.

zoning regulations

Local laws that control land use and development.