Demography is the study of populations — their size, structure, and distribution, and the processes through which they change. — NCERT
2.1 Population Size and Growth
India is the world's most populous country (over 1.4 billion).
- Census — conducted every 10 years; primary source of demographic data
- Growth rate has declined from about 2.2% (1971–81) to below 1% recently
- Youth bulge — a large proportion under 35 creates opportunities and pressures on education and employment
Key terms: population density, growth rate, census, dependency ratio
2.2 Age Structure
Age composition is shown through population pyramids:
- Broad base — high proportion of children (typical of developing countries)
- Narrowing top — fewer elderly due to lower life expectancy historically
- Transition — base is narrowing as fertility falls and life expectancy rises
The dependency ratio (ratio of dependents to working-age population) affects economic planning.
2.3 Sex Ratio
Sex ratio = number of females per 1,000 males.
- National sex ratio has improved but remains below equality (around 940–950)
- Child sex ratio (0–6 years) has been a concern due to son preference and sex-selective practices
- Regional variation — some states fare better (Kerala, Tamil Nadu) than others (Haryana, Punjab)
Causes include son preference, dowry, inheritance norms, and access to technology.
2.4 Birth and Death Rates
- Crude birth rate (CBR) — births per 1,000 population per year; has fallen significantly
- Crude death rate (CDR) — deaths per 1,000 population; also declined due to better healthcare
- Natural growth = CBR minus CDR
- Infant mortality rate (IMR) — deaths of infants under one year per 1,000 live births; a key indicator of development
2.5 Literacy
Literacy rates have risen sharply since independence:
- Overall literacy crossed 75% (Census 2011)
- Gender gap persists — female literacy lags behind male literacy
- Regional disparities — Kerala highest; some northern states lower
- Literacy is linked to employment, health outcomes, and political participation
2.6 Migration
Migration — movement of people across boundaries for work, marriage, or displacement.
Types:
- Rural to urban — largest flow; driven by landlessness, unemployment, and urban opportunities
- Inter-state — uneven development creates labour migration (e.g. to Maharashtra, Delhi)
- International — skilled migration to West; Gulf migration from Kerala and other states
- Distress migration — caused by drought, floods, or conflict
Migration reshapes cities, families, and regional economies.
Chapter Summary
- India has a large, slowing-growing population with a youthful age structure
- Sex ratio and child sex ratio reflect gender inequality
- Birth and death rates have declined; IMR is a key development indicator
- Literacy has improved but gender and regional gaps remain
- Migration — especially rural-to-urban — is a major demographic process
Exercises (NCERT)
- Exercise 1 — population size, growth, and age structure
- Exercise 2 — sex ratio and its causes
- Exercise 3 — literacy and migration patterns