AP Human Geography Cheat Sheet 2026
Unit 1 — Thinking Geographically
| Term | Definition |
|---|---|
| Absolute location | Exact coordinates (latitude/longitude) |
| Relative location | Location described in relation to other places |
| Sense of place | Subjective feelings associated with a location |
| Region | Area with shared characteristics; formal, functional, or vernacular |
| Scale | Relationship between map distance and actual distance |
| Diffusion | Spread of ideas/innovations across space |
| Hearth | Place of origin of an innovation or cultural trait |
| Contagious diffusion | Spreads to adjacent areas (like a disease) |
| Hierarchical diffusion | Spreads from large cities to smaller ones (top-down) |
| Stimulus diffusion | Underlying idea spreads but adapted to local context |
| Relocation diffusion | Spreads through physical movement of people |
| GIS | Geographic Information System — maps layered digital data |
| Remote sensing | Collecting data from satellites or aircraft |
Unit 2 — Population & Migration
| Term | Definition |
|---|---|
| CBR / CDR | Crude Birth Rate / Crude Death Rate (per 1,000 people) |
| NIR | Natural Increase Rate = CBR − CDR; population growth without migration |
| TFR | Total Fertility Rate — average children per woman; replacement level ≈ 2.1 |
| Demographic Transition Model (DTM) | 4–5 stages from high birth/death rates to low birth/death rates |
| Stage 1 DTM | High CBR, high CDR; pre-industrial; population stable |
| Stage 2 DTM | High CBR, falling CDR; rapid population growth |
| Stage 3 DTM | Falling CBR, low CDR; slowing growth; industrializing |
| Stage 4 DTM | Low CBR, low CDR; stable/slow growth; developed countries |
| Stage 5 DTM | CBR below CDR; population decline (Japan, Germany) |
| Population pyramid | Bar chart showing age-sex structure; wide base = young/growing population |
| Dependency ratio | (Youth + Elderly) / Working-age × 100 |
| Push factors | Conditions that drive people away (poverty, war, drought) |
| Pull factors | Conditions that attract people (jobs, safety, family) |
| Ravenstein's Laws | Most migrants move short distances; step migration; urban destinations |
| Forced migration | Involuntary movement (refugees, slavery, environmental displacement) |
| Voluntary migration | By choice, usually economic reasons |
| Internally Displaced Person (IDP) | Forced from home but remains within own country |
| Refugee | Forced to cross international border to escape persecution |
| Remittances | Money sent by migrants back to home country |
Unit 3 — Cultural Patterns & Processes
| Term | Definition |
|---|---|
| Culture | Shared beliefs, values, practices of a group |
| Cultural landscape | Human modification of natural environment; reflects culture |
| Folk culture | Small, homogeneous groups; slow to change; oral tradition |
| Popular culture | Widespread; changes rapidly; driven by mass media |
| Lingua franca | Common language used between speakers of different languages |
| Creole / Pidgin | Language that develops from contact between two languages |
| Universalizing religion | Seeks to convert all; global spread (Christianity, Islam, Buddhism) |
| Ethnic religion | Tied to specific group/place; doesn't seek converts (Judaism, Hinduism) |
| Syncretism | Blending of two or more cultural traditions |
| Acculturation | Adopting traits of a dominant culture while retaining own |
| Assimilation | Complete absorption into dominant culture; loss of original culture |
| Cultural imperialism | Dominant culture displaces or undermines local cultures |
| Sequent occupance | Successive cultures leave their imprint on the landscape |
Unit 4 — Political Patterns & Processes
| Term | Definition |
|---|---|
| State | Politically organized territory with sovereignty |
| Nation | Group sharing cultural identity (not necessarily a state) |
| Nation-state | Nation and state coincide; most governments aspire to this |
| Sovereignty | Supreme authority over a defined territory |
| Centripetal forces | Unite a state (common language, religion, national identity) |
| Centrifugal forces | Divide a state (ethnic conflict, regional inequality) |
| Devolution | Transfer of power from central to regional governments |
| Supranationalism | Nations cede some sovereignty to international body (EU, UN) |
| Gerrymandering | Drawing district boundaries to favor a party or group |
| Boundary types | Geometric: straight lines. Physical: rivers, mountains. Cultural: religion, language |
| Antecedent boundary | Drawn before area was settled (many African borders) |
| Subsequent boundary | Drawn after settlement, reflects cultural divisions |
| Shatterbelt | Region caught between competing powers; politically fragmented |
| Heartland theory | Mackinder: control of Eurasian interior = world power |
Unit 5 — Agriculture & Rural Land Use
| Term | Definition |
|---|---|
| Subsistence agriculture | Producing only enough food for the farmer's family |
| Commercial agriculture | Producing crops for sale in markets |
| Intensive agriculture | High inputs (labor/capital) per unit of land; near urban areas |
| Extensive agriculture | Low inputs per unit; large areas; remote locations |
| Von Thünen model | Agricultural land use rings around a market city; closer = more intensive |
| Green Revolution | 1960s–70s: HYV seeds, irrigation, fertilizers → ↑ food production in LDCs |
| GMO (Genetically Modified Organism) | Crops engineered for higher yield or pest resistance |
| Monoculture | Growing a single crop over large areas; efficient but vulnerable |
| Agribusiness | Large-scale commercial farming integrated with processing/distribution |
| Fair trade | Paying farmers in LDCs higher prices to improve living standards |
Unit 6 — Cities & Urban Land Use
| Term | Definition |
|---|---|
| Urbanization | Increase in % of population living in cities |
| Primate city | City > twice as large as next largest; dominates country (Bangkok, Paris) |
| Rank-size rule | nth largest city = 1/n of largest city's population |
| Central Place Theory (Christaller) | Explains size and distribution of cities; larger cities serve larger market areas |
| CBD (Central Business District) | Core of city; high land values, offices, retail, skyscrapers |
| Concentric Zone Model | Burgess: rings of land use expanding from CBD outward |
| Sector Model | Hoyt: wedge-shaped sectors along transportation routes |
| Multiple Nuclei Model | Harris & Ullman: several nodes of activity, not one center |
| Gentrification | Higher-income residents move into low-income urban area → rising rents, displacement |
| Suburbanization | Movement from city core to surrounding suburbs; enabled by cars |
| Edge city | Large suburban node with offices, retail, jobs; outside traditional CBD |
| Squatter settlements (informal housing) | Self-built housing lacking legal title, services; common in LDC cities |
Unit 7 — Industrial & Economic Development
| Term | Definition |
|---|---|
| GDP per capita | Total economic output per person; common development indicator |
| HDI (Human Development Index) | Combines income, education, life expectancy |
| Core-periphery model | Wealthy core countries exploit less-developed periphery |
| Wallerstein's World Systems Theory | Core, semi-periphery, periphery; global economic hierarchy |
| Rostow's Stages of Development | 5 stages from traditional to high mass consumption |
| Dependency theory | LDCs remain poor because of exploitation by MDCs; colonialism's legacy |
| EPZ (Export Processing Zone) | Designated area with tax incentives to attract foreign manufacturing; common in Asia and Latin America |
| Maquiladora | Foreign-owned factory in Mexico near US border; assembly for export |
| Outsourcing | Moving production to cheaper labor markets |
| Bulk-gaining industry | Final product heavier than inputs; locate near market (beverages, auto assembly) |
| Bulk-reducing industry | Final product lighter than inputs; locate near raw materials (steel, copper) |
| Footloose industry | Not tied to specific location; can locate anywhere (tech, software) |
| Weber's least-cost theory | Industries locate where transportation + labor costs are minimized |
| Agglomeration | Clustering of related industries in one area; shared infrastructure, labor pool |
| Deindustrialization | Loss of manufacturing jobs in developed countries; shift to service economy |