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Important Topics for UPSC Prelims 2026

Important Topics for UPSC Prelims 2026 – Legacy IAS

Important Topics for UPSC Prelims 2026

Curated & Structured by Legacy IAS, Bangalore

7 Subjects Covered Priority-Mapped Exam-Ready Format
© 2025 Legacy IAS — For Aspirant Use Only

Table of Contents

01 Indian Polity & GovernanceConstitution, Bodies, Federalism 02 EconomyBanking, Fiscal Policy, External Sector 03 History & CultureAncient, Medieval, Modern, Art 04 GeographyPhysical, Indian, Human 05 Environment & EcologyBiodiversity, Climate, Laws 06 Science & TechnologySpace, Biotech, Defence, IT 07 CSAT (Paper II)Comprehension, Reasoning, Numeracy
01

Indian Polity & GovernancePrelims Weightage: Very High

Subject Overview — Polity
Indian Polity
Fundamental Rights & DPSP Parliament Judiciary Constitutional Bodies Federalism Local Governance Amendments & Schedules Governance & Transparency

Fundamental Rights, DPSP & Fundamental Duties

Fundamental Rights (Articles 12–35) High Priority
Asked every year in some form Link: Recent SC judgments on Art. 19, 21
  • Right to Equality (Art. 14–18) — Reasonable classification tests
  • Right to Freedom (Art. 19) — Six freedoms and reasonable restrictions
  • Right against Exploitation (Art. 23–24)
  • Right to Freedom of Religion (Art. 25–28)
  • Cultural & Educational Rights (Art. 29–30)
  • Right to Constitutional Remedies (Art. 32) — Five writs: Habeas Corpus, Mandamus, Certiorari, Prohibition, Quo Warranto
  • Distinction between Art. 32 and Art. 226
Directive Principles of State Policy High Priority
Tricky statement-based questions PYQ: FR vs DPSP relationship asked multiple times
  • Classification — Socialist, Gandhian, Liberal-intellectual
  • Enforceability vs non-enforceability distinction
  • Relationship between FRs and DPSPs — Minerva Mills case
  • Amendments that gave precedence to DPSPs over FRs
Fundamental Duties (Art. 51A) Medium Priority
  • 11 duties added by 42nd Amendment — Key list recall
  • Non-justiciable but legally enforceable through legislation
  • Verma Committee recommendations

Parliament — Structure, Powers & Procedures

Parliamentary Procedures & Legislation High Priority
Asked almost every year Link: Recent Bills, Joint Sittings, Ordinances
  • Lok Sabha vs Rajya Sabha — Composition, tenure, special powers
  • Types of Bills — Money Bill vs Financial Bill vs Ordinary Bill
  • Budget process — Stages, Guillotine, Appropriation Bill, Finance Bill
  • Question Hour, Zero Hour, Calling Attention Motion
  • Joint Sitting (Art. 108) — Conditions & exceptions
  • Parliamentary Committees — PAC, Estimates, DRSCs
  • Anti-Defection Law (Tenth Schedule) — Provisions & exceptions
  • Parliamentary Privileges — Breach & contempt
Feature Money Bill Financial Bill (Type I) Ordinary Bill
Introduced in Lok Sabha only Lok Sabha only Either House
President’s prior recommendation Required Required Not required
Rajya Sabha power 14-day recommendation only Can amend / reject Can amend / reject
Joint Sitting Not applicable Possible Possible
Speaker’s certification Required Not required Not required

Union Executive

President, PM & Council of Ministers High Priority
  • President — Election (Electoral College, value of votes), emergency powers
  • Veto powers — Absolute, Suspensive, Pocket veto
  • Ordinance-making power (Art. 123) — Scope, limitations, judicial review
  • Vice-President — Election, removal, functions
  • PM & Council of Ministers — Collective responsibility, individual responsibility
  • Attorney General — Appointment, functions, limitations

Judiciary

Supreme Court, High Courts & Judicial Review High Priority
Link: Collegium debates, PIL trends, judicial overreach
  • SC — Composition, original / appellate / advisory jurisdiction
  • Collegium system vs NJAC — Landmark cases
  • Judicial Review vs Judicial Activism
  • Public Interest Litigation (PIL) — Evolution & significance
  • High Courts — Powers under Art. 226, supervisory jurisdiction
  • Removal of judges — Impeachment process
  • Landmark judgments: Kesavananda Bharati, Golaknath, Minerva Mills

Federalism & Centre-State Relations

Centre-State Relations & Emergency Provisions High Priority
  • 7th Schedule — Union, State, Concurrent lists (key entries)
  • Legislative, Administrative & Financial relations
  • Inter-State Council, Zonal Councils
  • Finance Commission — Role, composition, recommendations
  • GST Council — Structure, voting, dispute resolution
  • Emergency provisions — National (352), State (356), Financial (360)
  • President’s Rule — Procedure, effects, judicial review (SR Bommai case)

Constitutional & Statutory Bodies

Key Bodies — Constitutional vs Non-Constitutional High Priority
Frequently tested via statement-based Qs
  • Constitutional: Election Commission, CAG, UPSC, Finance Commission, National SC/ST Commissions
  • Non-Constitutional / Statutory: NITI Aayog, NHRC, CVC, Lokpal & Lokayuktas, CBI, NIA
  • Composition, appointment, tenure, removal — for each body
  • Key differences between constitutional and statutory status

Local Self-Government (73rd & 74th Amendments)

Panchayati Raj & Urban Local Bodies Medium Priority
  • Three-tier Panchayati Raj — Gram, Block, District levels
  • Gram Sabha powers, 11th Schedule subjects
  • State Election Commission, State Finance Commission
  • Reservation provisions — SC/ST/OBC, women (not less than 1/3)
  • Urban bodies — Municipal Corporations, Municipalities, Nagar Panchayats
  • 12th Schedule subjects

Governance, Transparency & Accountability

RTI, E-Governance & Accountability Medium Priority
Link: Digital India, recent RTI amendments
  • Right to Information Act 2005 — Provisions, exemptions, amendments
  • Citizen’s Charter — Concept and implementation
  • E-Governance initiatives — Digital India, e-Courts, DigiLocker
  • Social audit mechanisms
  • Whistleblower Protection Act
⚡ Rapid Revision — Key Articles for Prelims
  • Art. 14 — Equality before law & equal protection of laws
  • Art. 19 — Six freedoms (speech, assembly, association, movement, residence, profession)
  • Art. 21 — Right to life and personal liberty
  • Art. 32 — Right to constitutional remedies (Ambedkar: “Heart & soul of the Constitution”)
  • Art. 123 — Ordinance-making power of the President
  • Art. 356 — President’s Rule in a State
  • Art. 368 — Procedure for Constitutional Amendment
  • Art. 370 — Special status of J&K (abrogated)
02

EconomyPrelims Weightage: Very High

Subject Overview — Economy
Indian Economy
Banking & Monetary Policy Fiscal Policy & Budget National Income Concepts External Sector Agriculture & Inclusive Growth

National Income & Core Concepts

GDP, Inflation & Employment High Priority
Foundation for all economy questions PYQ: GDP deflator, CPI vs WPI asked repeatedly
  • GDP, GNP, NDP, NNP — Formulae & distinctions
  • Real GDP vs Nominal GDP — Base year concept
  • GDP Deflator — Formula & significance
  • Inflation measures — CPI (Combined, IW, AL) vs WPI
  • Core inflation, Stagflation, Deflation, Disinflation
  • Types of unemployment — Structural, cyclical, disguised, seasonal
  • Fiscal deficit, Revenue deficit, Primary deficit — Definitions & implications
  • Balance of Payments — Current Account vs Capital Account components
  • Exchange rate systems — Fixed, Floating, Managed float

Banking & Monetary Policy

RBI, Policy Rates & Financial System High Priority
Link: Recent MPC decisions, CBDC rollout
  • RBI — Functions (monetary authority, regulator, issuer of currency, banker to govt)
  • Monetary Policy Committee (MPC) — Composition, voting, inflation targeting
  • Policy rates — Repo, Reverse Repo, MSF, Bank Rate, SDF
  • CRR & SLR — Differences, effects on money supply
  • Open Market Operations (OMOs), LAF
  • CBDC (Digital Rupee) — e-Rupee pilot features
  • NPAs, Basel III norms, Prompt Corrective Action framework
  • Financial inclusion — Jan Dhan, PM Mudra, PM Jeevan Jyoti
Flowchart — How Repo Rate Cut Affects Economy
RBI Cuts Repo Rate
→
Banks Borrow Cheaper from RBI
→
Lower Lending Rates
→
More Borrowing & Spending
→
Economic Growth ↑

Fiscal Policy & Union Budget

Budget, Taxes & Fiscal Management High Priority
Link: Union Budget 2025-26 provisions
  • Union Budget structure — Revenue & Capital (Receipts & Expenditure)
  • Consolidated Fund, Contingency Fund, Public Account
  • Direct vs Indirect taxes — Classification & examples
  • GST — Structure, Council, compensation cess, rate slabs
  • FRBM Act — Targets, amendments, escape clauses
  • Subsidies — Food, fertilizer, fuel — Rationalization trends
  • Public debt — Internal vs external, ways & means advances

External Sector & International Institutions

International Trade, FDI & Global Institutions High Priority
  • IMF — Functions, SDR, quota system, India’s role
  • World Bank Group — IBRD, IDA, IFC, MIGA, ICSID
  • WTO — Structure, dispute settlement, trade rounds
  • FDI vs FPI — Definitions, routes (automatic & approval)
  • Trade agreements — FTA, CEPA, CECA, RCEP
  • Currency depreciation vs devaluation — Causes & effects

Agriculture & Inclusive Growth

MSP, Food Security & Rural Schemes Medium Priority
Link: MSP debates, new agricultural policies
  • MSP mechanism — CACP, cost concepts (A2, A2+FL, C2)
  • Food security — National Food Security Act, PDS reform
  • Crop insurance — PM Fasal Bima Yojana
  • Agricultural credit — KCC, NABARD role
  • SHGs & microfinance — Models, impact
  • Rural employment — MGNREGA provisions & challenges
⚡ Rapid Revision — Economy Must-Know Terms
  • Fiscal Deficit = Total Expenditure − Total Receipts (excluding borrowings)
  • Revenue Deficit = Revenue Expenditure − Revenue Receipts
  • Primary Deficit = Fiscal Deficit − Interest Payments
  • CRR: % of deposits banks keep with RBI (no interest)
  • SLR: % of deposits banks invest in govt. securities
  • Repo Rate: Rate at which RBI lends to banks (short-term)
03

History & Art & CulturePrelims Weightage: High

Subject Overview — History
History & Culture
Ancient India Medieval India Modern India National Movement Art & Culture
Trend Alert: UPSC increasingly asks analytical, map-based, and culture-linked history questions. Rote learning of dates is less important than understanding causes, impacts, and connections.

Ancient India

Indus Valley (Harappan) Civilisation High Priority
PYQ: Site-feature matching is a favourite pattern
  • Major sites & unique features — Dholavira (water management), Lothal (dockyard), Kalibangan (fire altars)
  • Urban planning — Grid pattern, drainage system, granaries
  • Trade with Mesopotamia — Seals as evidence
  • Undeciphered script — Significance in understanding civilisation
  • Religious practices — Mother Goddess, Pashupati seal
  • Decline theories — Climate, tectonic, Aryan invasion (debated)
Vedic Period & Mahajanapadas Medium Priority
  • Early vs Later Vedic — Changes in polity, economy, religion, women’s status
  • Sabha & Samiti — Transition from tribal democracy to monarchy
  • Vedic literature — Four Vedas, Upanishads, Aranyakas
  • 16 Mahajanapadas — Republics vs monarchies, capitals
  • Magadha’s rise — Iron deposits, elephants, strategic rivers
Buddhism & Jainism High Priority
PYQ: Buddhist councils, Jain doctrines frequently asked
  • Buddha — Four Noble Truths, Eightfold Path, Middle Path
  • Buddhist Councils — Location, patron, outcomes (all 4 councils)
  • Hinayana vs Mahayana — Key differences
  • Jain Triratna (Right Faith, Knowledge, Conduct)
  • Spread abroad — Ashoka’s role, Silk Route, SE Asia
Mauryan & Gupta Empires High Priority
  • Maurya — Chandragupta, Ashoka’s Dhamma, Arthashastra, edicts classification
  • Provincial & local administration under Mauryas
  • Gupta “Golden Age” — Aryabhata, Kalidasa, Nalanda, coinage
  • Temple architecture beginnings — Gupta-era structural temples
  • Decline causes of both empires
Sangam Age & South Indian Kingdoms Medium Priority
  • Chera, Chola, Pandya — Capitals, ports, administration
  • Sangam literature — Classification, key texts
  • Roman trade — Pepper, muslin, gold coins as evidence

Medieval India

Delhi Sultanate Medium Priority
  • Five dynasties — Slave, Khilji, Tughlaq, Sayyid, Lodi (key rulers per dynasty)
  • Alauddin Khilji — Market reforms, price control, espionage system
  • Muhammad bin Tughlaq — Token currency, capital shift, taxation experiments
  • Iqta system — Land revenue administration
  • Architecture — Qutub Minar, Alai Darwaza, Tughlaq style
Mughal Empire High Priority
  • Akbar — Mansabdari system, Sulh-i-Kul, Din-i-Ilahi, Todar Mal’s revenue system
  • Administration — Central, provincial, revenue structure
  • Mughal architecture — Taj Mahal, Red Fort, Buland Darwaza
  • Aurangzeb’s policies & their consequences
  • Causes of Mughal decline — Administrative, military, economic
Bhakti & Sufi Movements High Priority
PYQ: Saint-teaching matching is a common pattern
  • Nirguna vs Saguna traditions — Key distinction
  • Saints — Kabir, Guru Nanak, Tulsidas, Mirabai, Ramanuja, Shankaracharya
  • Sufi orders — Chishti (Ajmer), Suhrawardi, Naqshbandi, Qadiri
  • Social impact — Caste reform, vernacular literature
Vijayanagara & Bahmani Kingdoms Moderate
  • Vijayanagara — Administration, Hampi architecture, Krishnadevaraya
  • Battle of Talikota (1565) — Causes & consequences
  • Bahmani — Fragmentation into Deccan Sultanates

Modern India & National Movement

European Arrival & British Expansion Medium Priority
  • Portuguese, Dutch, English, French — Chronological arrival & settlements
  • Carnatic Wars — Anglo-French rivalry
  • Battle of Plassey (1757) & Buxar (1764) — Significance
  • Subsidiary Alliance, Doctrine of Lapse — Expansion strategies
Revolt of 1857 Medium Priority
  • Political, economic, military, religious causes
  • Centres & leaders — Delhi, Kanpur, Lucknow, Jhansi
  • Why it failed — Lack of coordination, limited geography
  • Consequences — End of Company rule, Queen’s Proclamation
Indian National Movement (1885–1947) High Priority
3–5 questions expected every year
  • INC formation (1885) — Moderate phase demands & methods
  • Extremist phase — Bal, Pal, Lal; Swadeshi Movement
  • Home Rule Movement — Tilak & Annie Besant
  • Gandhian Era — Non-Cooperation (1920), Civil Disobedience (1930), Quit India (1942)
  • Revolutionary movements — HSRA, Bhagat Singh, Surya Sen
  • Subhas Chandra Bose & INA — Forward Bloc, Azad Hind
  • Cabinet Mission, Mountbatten Plan, Partition
Socio-Religious Reform Movements Medium Priority
  • Brahmo Samaj (Raja Ram Mohan Roy) — Abolition of Sati
  • Arya Samaj (Dayanand Saraswati) — Shuddhi movement
  • Aligarh Movement (Sir Syed Ahmad Khan)
  • Young Bengal (Henry Vivian Derozio)
  • Prarthana Samaj, Ramakrishna Mission, Theosophical Society
Constitutional Development under British Rule High Priority
PYQ: Act-provision matching asked frequently
  • Regulating Act 1773 — SC at Calcutta, Governor-General
  • Charter Acts (1813, 1833, 1853) — Progressive reforms
  • Indian Councils Acts (1861, 1892, 1909) — Morley-Minto, separate electorates
  • GoI Act 1919 — Dyarchy, bicameral legislature
  • GoI Act 1935 — Provincial autonomy, federal structure, All-India Federation (never realised)
  • India Independence Act 1947 — Key provisions
Act / Year Key Provision Significance
Regulating Act, 1773 Governor-General of Bengal; SC at Calcutta First step to centralise British administration
Charter Act, 1833 Governor-General of India; ended Company’s trade monopoly Centralised power over all British India
Indian Councils Act, 1909 Separate electorates for Muslims Sowed seeds of communal politics
GoI Act, 1919 Dyarchy in provinces First introduction of responsible govt. (partial)
GoI Act, 1935 Provincial autonomy; Federal Court Primary source for Indian Constitution

Art & Culture

Indian Architecture — Stupas, Temples & Islamic High Priority
PYQ: Style-feature matching is very common
  • Stupa architecture — Sanchi, Bharhut, Amaravati; structural components
  • Rock-cut architecture — Ajanta (paintings), Ellora (Kailasa temple), Barabar caves
  • Temple styles — Nagara (North), Dravida (South), Vesara (Deccan)
  • Components — Garbhagriha, Shikhara, Mandapa, Vimana, Gopuram
  • Indo-Islamic architecture — Arches, domes, minarets, pietra dura
Paintings, Dances & Music Medium Priority
  • Painting schools — Ajanta murals, Mughal, Rajput, Pahari, Tanjore
  • Classical dances — Bharatanatyam, Kathak, Kathakali, Odissi, Manipuri, Kuchipudi, Mohiniyattam, Sattriya
  • Hindustani vs Carnatic music — Key differences, Raga system
UNESCO World Heritage Sites in India High Priority
Link: Newly inscribed sites in 2024-25
  • Cultural vs Natural vs Mixed sites — Classification
  • Recently added sites — Keep updated via current affairs
  • Selection criteria — Outstanding Universal Value (OUV)
  • Tentative list of India — Sites under consideration
Feature Nagara (North) Dravida (South) Vesara (Deccan)
Tower Shikhara (curvilinear) Vimana (pyramidal) Hybrid of both
Gateway Simple entrance Elaborate Gopuram Moderate
Compound No boundary wall High compound wall Variable
Region Vindhyas to Himalayas Krishna River to Kanyakumari Karnataka, Maharashtra
Examples Khajuraho, Konark Brihadeeswarar, Meenakshi Hoysala temples (Belur, Halebid)
04

GeographyPrelims Weightage: High

Subject Overview — Geography
Geography
Earth’s Interior & Geomorphology Climatology Oceanography Indian Physiography Indian Climate & Agriculture Human Geography

Physical Geography — Earth, Landforms & Climate

Earth’s Interior & Rocks Medium Priority
  • Crust, Mantle, Core — Composition, density, discontinuities (Moho, Gutenberg)
  • Seismic waves — P-waves, S-waves, surface waves; shadow zones
  • Rock types — Igneous, Sedimentary, Metamorphic
  • Rock cycle — Processes & interconversions
Geomorphology — Plate Tectonics & Landforms High Priority
PYQ: Plate boundaries, landform processes asked often
  • Plate tectonics — Divergent, convergent, transform boundaries
  • Continental drift theory — Evidences (Wegener)
  • Sea-floor spreading — Mid-oceanic ridges
  • Earthquakes — Focus, epicentre, Richter scale, distribution
  • Volcanoes — Types (shield, composite, cinder cone), Ring of Fire
  • Weathering — Physical, chemical, biological agents
  • Erosion & deposition — Fluvial, aeolian, glacial landforms
Climatology — Atmosphere, Winds & Cyclones High Priority
Link: El Niño/La Niña impact on monsoon, climate change
  • Atmosphere layers — Troposphere, Stratosphere, Mesosphere, Thermosphere
  • Heat budget — Insolation, albedo, terrestrial radiation
  • Pressure belts & planetary wind systems
  • Jet streams — STJ, Somali Jet, their role in Indian monsoon
  • Tropical cyclones vs temperate cyclones — Structure, formation, tracks
  • El Niño, La Niña, ENSO, IOD — Mechanisms & impacts
  • Global warming, greenhouse effect, carbon cycle
Oceanography Medium Priority
  • Ocean floor relief — Continental shelf, slope, abyssal plains, trenches
  • Ocean currents — Warm & cold, gyres, Coriolis effect
  • Tides — Spring, neap; gravitational pull of Moon & Sun
  • Salinity & temperature distribution patterns
  • Upwelling & downwelling — Significance for marine life

Indian Geography — Physical, Climate & Resources

Physiography of India High Priority
PYQ: Map-based questions on passes, plateaus, rivers
  • Himalayan divisions — Greater Himalaya, Lesser Himalaya (Pir Panjal, Dhauladhar), Shivaliks
  • Northern Plains — Bhabar, Terai, Bhangar, Khadar
  • Peninsular Plateau — Deccan Plateau, Malwa, Chotanagpur
  • Western & Eastern Ghats — Comparison, passes (Palghat, Bhor, Thal)
  • Coastal plains — Konkan, Malabar, Coromandel, Northern Circars
  • Islands — Andaman & Nicobar, Lakshadweep (coral vs volcanic)
  • Important mountain passes — Karakoram, Rohtang, Nathu La, Bomdi La
Indian Drainage System High Priority
  • Himalayan rivers — Indus system, Ganga system, Brahmaputra; antecedent rivers
  • Peninsular rivers — Godavari, Krishna, Narmada, Tapi; east-flowing vs west-flowing
  • Tributaries — Origin and confluence points (high PYQ recall)
  • River interlinking projects — Ken-Betwa, Godavari-Krishna
  • Major dams & reservoirs — State-wise mapping
Indian Climate & Monsoons High Priority
  • Factors affecting Indian climate — Latitude, altitude, distance from sea, ocean currents
  • Southwest monsoon — Mechanism, Arabian Sea & Bay of Bengal branches
  • Northeast monsoon — Tamil Nadu coast rainfall
  • Western disturbances — Winter rainfall in north India
  • Cyclone-prone zones — Bay of Bengal, Arabian Sea
  • Climatic regions of India — Koppen classification
Soils, Agriculture & Resources High Priority
  • Soil types — Alluvial, Black (Regur), Red, Laterite, Mountain, Desert
  • Soil erosion & conservation — Sheet, rill, gully; contour ploughing, terracing
  • Cropping seasons — Kharif, Rabi, Zaid (crop-season mapping)
  • Major crops & producing states — Rice, wheat, cotton, sugarcane, tea, coffee
  • Irrigation methods — Canal, well, tank; micro-irrigation trends
  • Minerals — Coal, iron ore, bauxite, manganese (belt-wise distribution)
  • Energy — Conventional vs non-conventional; solar & wind potential zones
  • Major ports, National Waterways, railway zones

Human Geography

Population & Economic Geography Moderate
  • Demographic transition model — Stages, India’s position
  • Population pyramid — Expansive, stable, constrictive types
  • Migration — Push & pull factors, rural-urban trends
  • Urbanisation — Trends, smart cities, census interpretation
  • Industrial location factors — Weber’s theory, SEZs, industrial corridors
⚡ Rapid Revision — Geography Quick Recall
  • Narmada & Tapi are the only major west-flowing peninsular rivers (flow through rift valleys)
  • Godavari = “Dakshin Ganga” — Largest peninsular river
  • El Niño = Warm Pacific → Weak Indian monsoon; La Niña = Cool Pacific → Strong monsoon
  • Black soil = Basaltic lava origin → Best for cotton (Regur)
  • Western Ghats = Higher & continuous; Eastern Ghats = Discontinuous & lower
05

Environment & EcologyPrelims Weightage: Very High (Rising Trend)

Trend Alert: Environment has emerged as the highest-weightage section in recent Prelims. Expect 15–20 questions. Focus on conceptual clarity + current-affairs integration.
Subject Overview — Environment
Environment & Ecology
Ecology Basics Biodiversity & Conservation Pollution Climate Change & Conventions Environmental Laws

Ecology — Core Concepts

Ecosystem Fundamentals High Priority
Foundation for all environment questions
  • Ecosystem components — Biotic (producers, consumers, decomposers) & Abiotic
  • Food chain & food web — Grazing chain vs detritus chain
  • Ecological pyramids — Energy (always upright), biomass, number
  • Biomes — Tundra, taiga, grasslands, deserts, tropical forests
  • Ecological succession — Primary & secondary; xerosere, hydrosere
  • Ecotone & edge effect — Definition & examples
  • Keystone species vs flagship species vs indicator species
Biodiversity High Priority
  • Three levels — Genetic, species, ecosystem diversity
  • Biodiversity hotspots — 36 global (4 in India: Western Ghats, Eastern Himalayas, Indo-Burma, Sundaland)
  • IUCN Red List categories — CR, EN, VU, NT, LC
  • Endemic vs exotic species; invasive species examples

Biodiversity Conservation

Protected Areas & Conservation Programmes High Priority
Link: New tiger reserves, Project Cheetah updates, Ramsar sites PYQ: Park-state matching, Ramsar sites asked frequently
  • In-situ conservation — National Parks, Wildlife Sanctuaries, Biosphere Reserves
  • Ex-situ conservation — Zoos, seed banks, botanical gardens, cryopreservation
  • Wildlife corridors — Concept, examples in India
  • Project Tiger, Project Elephant, Project Cheetah — Status & updates
  • Ramsar Wetlands — Criteria, Indian sites (keep updated)
  • UNESCO Biosphere Reserves in India — Complete list
  • Man & Biosphere Programme

Environmental Pollution

Air, Water & Waste Pollution Medium Priority
  • Air pollutants — Primary (SO₂, CO, PM) vs secondary (ozone, PAN)
  • Water pollution — Sources, BOD, COD, eutrophication
  • Solid waste management — Rules, categories, disposal methods
  • Plastic pollution — SUP ban, extended producer responsibility
  • E-waste — Rules & management
  • Noise pollution — Standards, CPCB norms

Climate Change & International Conventions

Global Climate Governance High Priority
Link: Latest COP outcomes, India’s NDC updates
  • Greenhouse gases — CO₂, CH₄, N₂O, CFCs; Global Warming Potential (GWP)
  • Carbon sequestration — Biological & geological methods
  • Carbon trading — Cap-and-trade, carbon credits, Article 6 of Paris Agreement
  • UNFCCC → Kyoto Protocol → Paris Agreement — Evolution & key principles
  • COP meetings — Recent outcomes & pledges
  • REDD+ mechanism — Forest-based climate mitigation
  • IPCC — Role, assessment reports
  • India’s climate commitments — NDCs, net-zero target, ISA, CDRI
Flowchart — Evolution of Global Climate Governance
UNFCCC (1992)
→
Kyoto Protocol (1997)
→
Bali Action Plan (2007)
→
Paris Agreement (2015)
→
Glasgow Pact & Beyond

Environmental Laws in India

Key Environmental Legislation High Priority
  • Environment Protection Act 1986 — Umbrella legislation
  • Wildlife Protection Act 1972 — Schedules I–VI, NBWL
  • Forest Conservation Act 1980 — Diversion of forest land
  • Biological Diversity Act 2002 — NBA, SBBs, BMCs
  • National Green Tribunal (NGT) — Powers, jurisdiction, recent orders
  • EIA notification — Process, categories (A & B), public hearing
  • Coastal Regulation Zone (CRZ) rules
06

Science & TechnologyPrelims Weightage: Moderate–High

Key Approach: S&T in Prelims is heavily current-affairs driven. Focus on applications and recent developments rather than theoretical depth.

Space Technology

ISRO Missions & Launch Vehicles High Priority
Link: Chandrayaan-3, Gaganyaan, Aditya-L1 updates
  • PSLV vs GSLV vs GSLV Mk-III (LVM3) — Payload, orbit capabilities
  • Cryogenic engine technology — Significance
  • Satellite types — Communication, remote sensing, navigation
  • NavIC (IRNSS) — Indian regional navigation system
  • Recent missions — Chandrayaan-3, Aditya-L1, Gaganyaan status
  • NISAR, SPADEX, Reusable Launch Vehicle
  • Private space sector — IN-SPACe, NewSpace India

Biotechnology

Genetic Engineering, Vaccines & Biotech Applications High Priority
  • DNA & RNA basics — Structure, replication, central dogma
  • Recombinant DNA technology — Process, applications
  • CRISPR-Cas9 — Gene editing mechanism, ethical concerns
  • mRNA vaccines — Technology, how they differ from traditional vaccines
  • Stem cells — Types, therapeutic potential
  • GM crops — Bt Cotton, GM Mustard debate, Cartagena Protocol
  • Biofortification — Golden Rice, iron-rich crops

Information Technology & Emerging Tech

AI, Blockchain, Quantum & Cyber High Priority
Link: India’s AI Mission, Digital India, IT Act amendments
  • Artificial Intelligence — Types (narrow, general), applications, India’s AI strategy
  • Machine Learning & Deep Learning — Basic concepts
  • Blockchain — Distributed ledger, consensus, crypto regulation in India
  • Quantum computing — Qubits, quantum supremacy, India’s National Quantum Mission
  • Cybersecurity — CERT-In, threats (ransomware, phishing), data protection laws
  • 5G & 6G — Spectrum, applications, India rollout

Defence & Nuclear Technology

Missiles, Nuclear & Defence R&D Medium Priority
  • Nuclear fission vs fusion — Principles, applications
  • Nuclear reactors — Types (PWR, BWR, PHWR, breeder), India’s three-stage programme
  • Ballistic vs cruise missiles — Agni, Prithvi, BrahMos, Nirbhay
  • Hypersonic technology — HGVs, HCMs
  • DRDO, ISRO, DAE — Key organisations & roles
  • Make in India (Defence) — Recent indigenisation milestones

Health & Emerging Technologies

Health Tech, Nanotech & Clean Energy Medium Priority
  • Vaccine platforms — Inactivated, live-attenuated, subunit, mRNA, viral vector
  • Nanotechnology — Applications in medicine, agriculture, environment
  • Robotics & automation — Surgical robots, industrial applications
  • Hydrogen fuel — Green, blue, grey hydrogen; National Green Hydrogen Mission
  • Renewable energy tech — Solar (perovskite), wind (offshore), battery storage
07

CSAT — Paper II (Qualifying)Minimum 33% Required (66.66/200)

Warning: Despite being qualifying, many serious aspirants fail CSAT due to underpreparation. Regular practice is essential — especially comprehension and basic numeracy.

Reading Comprehension

Passage-Based Questions High Priority — Highest Weightage in CSAT
  • Central idea identification — Theme vs detail
  • Tone & inference-based questions
  • Fact vs opinion distinction
  • Logical conclusions from given passage
  • Assumption-based questions
  • Vocabulary in context
  • Statement strengthening & weakening
  • Author’s perspective & attitude

Logical Reasoning & Analytical Ability

Logic, Puzzles & Reasoning High Priority
  • Syllogism — Venn diagram approach
  • Statement & conclusion / Statement & assumption
  • Cause & effect reasoning
  • Coding-decoding — Number & letter based
  • Blood relations — Family tree construction
  • Seating arrangement — Linear & circular
  • Direction sense
  • Data sufficiency
  • Analytical puzzles — Grouping, scheduling

Basic Numeracy (Class X Standard)

Quantitative Aptitude High Priority
  • Number system — Divisibility, LCM, HCF, remainders
  • Percentages, Ratio & Proportion, Averages
  • Profit & Loss, Simple & Compound Interest
  • Time & Work, Time-Speed-Distance, Boats & Streams
  • Probability — Basic problems
  • Permutation & Combination — Fundamental counting
  • Mixture & Alligation

Data Interpretation

Charts, Graphs & Tables Medium Priority
  • Bar graphs — Single & grouped
  • Pie charts — Sector calculations
  • Line graphs — Trend analysis
  • Tables — Multi-variable extraction
  • Caselets — Data embedded in text

Decision Making & Problem Solving

Administrative & Ethical Scenarios Moderate
  • Administrative decision-making situations
  • Ethical dilemma resolution
  • Logical judgment-based problems
  • Choosing most practical & lawful course of action
⚡ CSAT — Preparation Strategy
  • Attempt RC passages first — they carry the highest marks
  • Practice 2 CSAT mock tests per week in the final 3 months
  • For numeracy: master short-cut methods for time-saving
  • Never skip CSAT preparation — even toppers have failed Paper II
  • Maintain 80+ accuracy in comprehension to ensure qualification

Legacy IAS, Bangalore

Important Topics for UPSC Prelims 2026 — Curated for Smart Revision & Prioritisation

© 2025 Legacy IAS. For aspirant use only. Not for redistribution.

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