What is population density? — The number of people per unit area. Formula: Population ÷ Area (km²). Sparse density: Siberia, Amazon. Dense: Bangladesh (1,100/km²), Netherlands. Influenced by climate, terrain, resources, and history.

What is the natural rate of population growth? — Birth rate − Death rate (expressed per 1,000 people per year). Positive = population growing. Does not include migration. Global average ~1% (2026).

What is the Demographic Transition Model (DTM)? — A 4 (or 5) stage model showing how birth rates and death rates change as a country develops economically. Stage 1 (high-high) → Stage 2 (high-falling DR) → Stage 3 (falling BR) → Stage 4 (low-low) → Stage 5 (BR < DR).

What are the 5 stages of the DTM? — Stage 1: High BR & DR, low growth (pre-industrial). Stage 2: DR falls, BR high, rapid growth (early industrial — many LICs). Stage 3: BR falls, slower growth (NICs). Stage 4: Low BR & DR, stable population (HICs). Stage 5: BR < DR, population decline (Japan, Germany).

What is a population pyramid? — A bar chart showing the age-sex structure of a population. Wide base: high birth rates, young population. Narrow base: low birth rates, aging population. Concave sides: high death rates. Shapes: Expanding pyramid (LICs), Constrictive (HICs).

What is the dependency ratio? — (Dependents ÷ Working-age population) × 100. Dependents = under 15 + over 64/65. A high ratio (LICs with many young) or aging populations (HICs with many elderly) both strain working-age people and government services.

What is life expectancy and what factors affect it? — The average number of years a person born in a given year is expected to live. High life expectancy correlates with: good healthcare, clean water, food security, peace, and higher incomes. Global average ≈ 73 years (2026).

What are push and pull factors in migration? — Push factors force people to leave: war, famine, unemployment, natural disasters, persecution. Pull factors attract people to a destination: employment, higher wages, safety, family, better services.

What is the difference between a refugee and a migrant? — Refugee: Forced to flee due to persecution, war, or violence — protected by international law (1951 Refugee Convention). Cannot safely return. Migrant: Chooses to move, usually for economic reasons. Not legally protected as a refugee.

What is urbanisation? — The increasing proportion of a population living in urban areas (towns and cities). Global urban population surpassed 50% for the first time in 2007. Now ~57%. Rapid urbanisation is occurring fastest in Africa and Asia.

What is a megacity? — A city with a population of 10 million or more. There are ~35+ megacities globally (2026). Examples: Tokyo (~37M), Delhi (~32M), Shanghai (~29M), São Paulo (~22M), Mexico City (~22M).

What is a squatter settlement / shanty town? — Informal housing built illegally on land that residents do not own. Characterized by poor quality housing, lack of clean water, sanitation, electricity, and security of tenure. Also called favelas (Brazil), bustees (India), barrios (Latin America).

What is GDP (Gross Domestic Product)? — The total monetary value of all goods and services produced in a country in a year. GDP per capita (GDP ÷ population) is used to compare living standards between countries. High GDP per capita ≈ Higher Income Country (HIC).

What is the Human Development Index (HDI)? — A composite development measure (0–1 scale) combining: Life expectancy, Education (mean + expected years of schooling), and GNI per capita (PPP). Developed by UNDP. HDI > 0.8 = very high.

What are HICs, MICs, and LICs? — World Bank income classifications: HIC (High Income Country): GDP per capita >$13,846. MIC (Middle Income Country): $1,136–$13,845. LIC (Low Income Country): <$1,136. LIC = often called LEDC or developing country.

What is the Brandt Line? — An imaginary line drawn in 1980 by the Brandt Commission dividing the world's richer North and poorer South. North (HICs) above the line; South (LICs/MICs) below. Now considered outdated due to rise of China, South Korea, and Gulf states.

What is globalisation? — The process by which countries become increasingly interconnected through trade, communication, migration, investment, and culture. Enabled by advances in transport, technology, and the internet. Reduces trade barriers; increases interdependence.

What are Transnational Corporations (TNCs)? — Companies that operate in multiple countries (also called Multinational Corporations/MNCs). Examples: Apple, Nike, Shell, Toyota, McDonald's. They invest in LICs/MICs for cheaper labour and resources — bringing jobs but also exploiting workers.

What is the rural-urban fringe? — The zone at the edge of a city where urban and rural land uses mix. Subject to urban sprawl — the outward expansion of cities. Features: housing estates, retail parks, business parks, airports.

What is counter-urbanisation? — The movement of people and businesses from cities to rural areas or smaller towns. Driven by: high urban costs, better transport links, remote working, desire for quality of life. Opposite of urbanisation. Common in HICs.

What is sustainable development? — Development that "meets the needs of the present without compromising the ability of future generations to meet their own needs" (Brundtland Commission, 1987). Balances economic growth, social equity, and environmental protection.

What are the UN Sustainable Development Goals (SDGs)? — 17 global goals adopted in 2015, targeting 2030. Includes: No Poverty, Zero Hunger, Good Health, Quality Education, Gender Equality, Clean Energy, Climate Action. Successor to the Millennium Development Goals (MDGs).

What is food security? — When all people at all times have physical, social, and economic access to sufficient, safe, and nutritious food. Currently ~820 million people are undernourished globally. Threatened by climate change, conflict, poverty, and population growth.

What is aid in development geography? — Money, goods, services, or expertise given by one country (or organization) to another to promote development or respond to a crisis. Types: Bilateral (government to government), Multilateral (through UN/World Bank), NGO aid (charities), Emergency aid (disaster relief).

What is fair trade? — A trading partnership and social movement that aims to achieve greater equity in international trade. Guarantees farmers and workers in LICs a minimum price for their products, safe conditions, and community investment. Examples: fair trade coffee, cocoa, bananas.