UPSC - CSE · Prelims and Mains
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Every article we publish, arranged by subject, with preparation guides and current affairs. Free to read.
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The whole syllabus, subject by subject
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GS I01
History
Modern India, World History, Art and Culture 212 articles→
GS I02
Geography
Physical Geography, Economic Geography, Human Geography, World Geography 115 articles→
GS I03
Society
6 articles→
GS II04
Polity
Constitution, Judiciary 35 articles→
GS II05
International Relations
1 article→
GS III06
Economy
Agriculture and Allied Sectors 22 articles→
GS III07
Environment
2 articles→
GS III08
Science & Tech
31 articles→
GS IV09
Ethics
1 article→
Prelims and Mains10
Current Affairs
Explained against the syllabus, month by month 170 articles→
Preparation guides
How to prepare, step by step
Practical guides on planning, sources, practice and revision for UPSC - CSE.
01
UPSC GS 4 Syllabus: Ethics, Integrity and Aptitude Explained
The full UPSC GS 4 syllabus for the ethics paper, what it has actually asked from 2019 to 2026, how…
02
UPSC Essay Topics Previous Years: Every Topic From 2007 to 2026
UPSC essay topics previous years list: all 138 topics from 2007 to 2026, year by year and by theme, how…
03
UPSC Essay Paper: Syllabus, Pattern and How to Write the Essay
The UPSC essay paper explained: official syllabus, pattern and marks, the 2025 and 2026 topics, and how to write and…
04
UPSC GS 3 Syllabus: Economy, Agriculture, Science, Environment and Security
The UPSC GS 3 syllabus for Mains in full: economy, agriculture, science, environment, disasters and security, with topic-wise weightage from…
05
UPSC GS 2 Syllabus: Polity, Governance, Social Justice and International Relations
The UPSC GS 2 syllabus for Mains in full: polity, governance, social justice and international relations, with topic-wise weightage from…
06
UPSC GS 1 Syllabus: History, Culture, Geography and Indian Society
The UPSC GS 1 syllabus for Mains in full: Indian culture, modern and world history, Indian society and geography, with…
07
UPSC CSAT Syllabus: Topics, Qualifying Marks and What the Paper Asks
The UPSC CSAT syllabus in full: what CSAT is, the maths, reasoning and comprehension topics, the 33 per cent qualifying…
08
UPSC Prelims Syllabus: Seven Subjects of GS Paper 1 and Their Weightage
The UPSC Prelims syllabus in full: the seven subjects of GS Paper 1, weightage from 1,500 past questions, the most…
09
UPSC Syllabus 2027: Prelims, CSAT, Mains and Official PDF
The full UPSC syllabus for Prelims, CSAT and Mains: the official text of every General Studies paper, the official PDF,…
Prelims Test Series 2027
Read here, then test yourself under exam conditions
Sectional tests to build each subject, monthly current affairs tests, and full-length mocks, with every option explained.
- 47tests
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- 12current affairs
- 20full-length
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- One current affairs paper of 100 questions
- The ₹49 is adjusted against any package
Science & Tech Non-Communicable Diseases: Heart Disease, Cancer, Diabetes and Chronic Lung Disease in India
Non-communicable diseases explained: cardiovascular diseases, hypertension, diabetes, obesity, types of cancer, causes of cancer and mental health.
Science & Tech Communicable Diseases: Bacterial, Viral, Protozoan and Vector-Borne Diseases in India
Communicable diseases explained: pathogens, diseases caused by bacteria and virus, malaria life cycle, dengue, kala azar and vector borne diseases.
Science & Tech Advanced Materials: Composites, Smart Materials, Superconductors and Rare Earths
Advanced materials explained: composites and carbon fibre, smart materials, superconductors, OLED, rare earth elements, semiconductors and 3D printing.
Science & Tech Nuclear Fission and Fusion: Radioactivity, Half-Life and Nuclear Reactors
Nuclear fission and fusion explained: radioactivity, half-life, binding energy, reactors, fast breeders, India's three-stage programme and ITER.
Science & Tech Electric Current and Magnetism: Ohm’s Law, Electromagnetic Induction and Transformers
Electric current explained: Ohm's law, resistance, heating effect, magnetic effects, electromagnetic induction, transformers and semiconductors.
Science & Tech Nanotechnology: Nanomaterials, Carbon Nanotubes and Applications
Nanotechnology explained: the nanoscale, nanoparticles and nanomaterials, carbon nanotubes, uses in medicine and farming, India's Nano Mission, and risks.
Science & Tech Electrochemistry: Electrolysis, Batteries, Lithium-Ion Cells and Fuel Cells
Electrochemistry explained: galvanic cells, the electrochemical series, electrolysis, lithium-ion and sodium-ion batteries, and hydrogen fuel cells.
Science & Tech Reflection and Refraction of Light: Total Internal Reflection, Dispersion and Optics
Reflection and refraction of light explained: mirrors, lenses, refractive index, total internal reflection, dispersion, scattering and the human eye.
Science & Tech Sound Waves: Speed of Sound, Doppler Effect, Ultrasound and SONAR
Sound waves explained: why they are mechanical and longitudinal, the speed of sound, echo, resonance, the Doppler effect, ultrasound, SONAR and noise.
Polity Article 239A and Union Territories With Legislatures: Puducherry, Jammu and Kashmir and Ladakh
Article 239A explained: the Puducherry Assembly, the Jammu and Kashmir Reorganisation Act 2019, the end of Article 370, and why Ladakh has no legislature.
Polity Union Territories of India: Articles 239 to 241, Administration and Delhi Under Article 239AA
Union territories of India explained: the list of eight with capitals, Articles 239 to 241, the Lieutenant Governor and Delhi under Article 239AA.
Science & Tech Heat and Thermodynamics: Laws of Thermodynamics, Specific Heat and Heat Transfer
Laws of thermodynamics explained with heat and temperature, specific heat capacity, latent heat, conduction, convection, radiation and engines.
Science & Tech Newton’s Laws of Motion and Gravitation: Force, Momentum and Satellites
Newton's laws of motion and gravitation explained: equations of motion, inertia, momentum, friction, the law of gravitation, g, satellites and tides.
Science & Tech Carbon and Its Compounds: Allotropes, Hydrocarbons, Polymers and Plastics
Carbon and its compounds explained: catenation, allotropes of carbon, hydrocarbons and fuels, soaps and detergents, polymers and plastic pollution.
Science & Tech Metals and Non-Metals: Reactivity Series, Metallurgy, Alloys and Corrosion
Metals and non-metals explained: properties, the reactivity series, metallurgy and mining, alloys, toxic metals, corrosion and rusting of iron.
Science & Tech Immunity and Vaccines: Immune System, Types of Immunity and Vaccination in India
Immunity explained: immune system, lymphatic system, types of immunity, antibody and antigen, types of vaccines and the national immunization schedule.
Science & Tech Endocrine System: Endocrine Glands, Hormones and Their Functions
Endocrine system explained: endocrine system diagram, pituitary gland diagram, thyroid gland diagram, hormones and their functions, insulin and glucagon.
Polity Sarkaria Commission and Punchhi Commission: Centre-State Relations and Cooperative Federalism
Sarkaria Commission and Punchhi Commission on Centre-State relations: recommendations, the Rajamannar Committee, Zonal Councils and cooperative federalism.
Polity GST Council Under Article 279A: Members, Weighted Voting, Functions and the 101st Amendment
GST Council explained: 101st Amendment, Article 279A, GST Council members and chairman, weighted voting, functions, compensation cess and Mohit Minerals.
Science & Tech Acids, Bases and Salts: pH Scale, Indicators and Everyday Salts
The pH scale explained with acids, bases and salts: indicators, pH of blood, acid rain, neutralisation, baking soda, bleaching powder, plaster of Paris.
Science & Tech Chemical Reactions and Chemical Bonding: Types, Redox, Catalysts and Smog
Chemical reactions and chemical bonding explained: ionic and covalent bonds, types of chemical reactions, redox, catalysts and photochemical smog.
Polity Finance Commission and Centre-State Financial Relations: Tax Distribution, Grants-in-Aid and the GST Council
Finance Commission under Article 280 explained, with tax distribution under Articles 268 to 271, grants under Articles 275 and 282, and the GST Council.
Polity Centre-State Administrative Relations: Article 263 Inter-State Council, All India Services and Articles 256 to 262
Article 263 and the Inter-State Council explained, with Union directions under Articles 256 and 257, All India Services, water disputes and CBI consent.
History Chalcolithic Age in India: Copper Age Cultures, Sites and Megalithic Culture
Chalcolithic Age in India, the Copper Age of farming villages: Ahar, Kayatha, Malwa and Jorwe cultures, Inamgaon, Daimabad and the megalithic culture.
History Neolithic Age in India: Tools, Sites, Pottery and Revolution
Neolithic Age in India, the New Stone Age from about 10,000 years ago: polished tools, pottery, pit houses, major sites and the Neolithic revolution.
Science & Tech Nervous System: Neuron, Nerve Impulse, Human Brain and Reflex Action
Human nervous system explained: nervous system diagram, neuron structure, synapse, parts of brain, reflex action and a labelled human brain diagram.
Science & Tech Excretory System: Human Kidney, Nephron Structure and Urine Formation
Human excretory system explained: excretory system diagram, nephron structure, urine formation, dialysis, kidney stones and kidney transplant.
History Mesolithic Age in India: Microliths, Sites and Rock Paintings
Mesolithic Age in India, the Middle Stone Age of 12,000 to 10,000 years ago: microliths, major sites, the rock paintings of Bhimbetka and daily life.
History Palaeolithic Age in India: Old Stone Age Tools, Phases and Sites
Palaeolithic Age in India, the Old Stone Age from two million to 12,000 years ago: its phases, stone tools, major sites and early human life.
Polity Seventh Schedule of Indian Constitution: Union, State and Concurrent Lists and Centre-State Legislative Relations
Seventh Schedule of Indian Constitution explained: Union, State and Concurrent Lists, residuary powers, Article 249 and Parliament in the State field.
Polity Lok Adalat, NALSA and Free Legal Aid in India: Legal Services Authorities Act and Gram Nyayalayas
Lok Adalat explained: the Legal Services Authorities Act, NALSA, who gets free legal aid, Permanent and National Lok Adalats, and Gram Nyayalayas.
Science & Tech Modern Periodic Table: History, Groups, Blocks and Periodic Trends
Modern periodic table explained: Mendeleev to Moseley, groups, periods and blocks, periodic trends, and element families from halogens to rare earths.
Science & Tech Atomic Structure: States of Matter, Bohr Model, Isotopes and Electronic Configuration
Atomic structure explained: states of matter, the Bohr model, quantum numbers, isotopes and isobars, and the rules of electronic configuration.
Polity High Courts in India: Judges, Jurisdiction, Tribunals and Subordinate Courts
High courts in India explained: the 25 courts, appointment and retirement at 62, Article 226 writs, Article 227, tribunals and the district courts below.
Polity Judicial Review in India: Basis, Basic Structure and Judicial Activism
Judicial review in India explained: its basis, Kesavananda Bharati and the basic structure, Minerva Mills, the Ninth Schedule and judicial activism.
Science & Tech Respiratory System: Human Lungs, Mechanism of Breathing and Gas Exchange
Human respiratory system explained: respiratory system diagram, mechanism of breathing, lung volumes, lung capacity and the oxygen dissociation curve.
Science & Tech Circulatory System: Human Heart, Blood, Blood Groups and Double Circulation
Circulatory system explained: the human heart diagram, blood and plasma, ABO and Rh blood groups, double circulation, ECG and blood pressure.
Polity Supreme Court Jurisdiction: Original, Writ, Appellate and Advisory Powers
Supreme Court jurisdiction explained: Article 131 disputes, Article 32 writs, appeals and special leave, Article 143 advice, curative petition and PIL.
Polity Supreme Court of India: Collegium System, Appointment, Tenure and Removal of Judges
Collegium system explained: how Supreme Court judges are appointed, their qualifications, tenure and salary, the NJAC verdict and how a judge is removed.
History Delhi Sultanate: Five Dynasties, Rulers, Timeline and Map, 1206 to 1526
Delhi Sultanate (1206 to 1526) for UPSC: the five dynasties and their rulers, timeline and map, the iqta system, Persian sources, decline and PYQs.
International Relations Maritime Security of India: Piracy, High Risk Area, Coastal Security and the IMO
Maritime security of India: Somali piracy and the High Risk Area, Anti-Piracy Act 2022, coastal security after 26/11, IFC-IOR, IPMDA, SAGAR and the IMO.
Science & Tech Vitamins and Minerals: Vitamin Deficiency Diseases, Malnutrition and Nutrition Programmes
Vitamin deficiency diseases for UPSC: fat- and water-soluble vitamins, iron and iodine, marasmus and kwashiorkor, food fortification and PM POSHAN.
Science & Tech Human Digestive System: Alimentary Canal, Digestive Enzymes and Balanced Diet
Human digestive system for UPSC: the alimentary canal organ by organ, digestive enzymes and where each acts, bile, villi, and a balanced diet.
Science & Tech Cell Cycle and Cell Division: Mitosis, Meiosis, Stem Cells and Cancer
Cell cycle and cell division: phases of the cell cycle, mitosis and meiosis compared, apoptosis, types of stem cells, stem cell therapy and cancer cells.
Science & Tech Cell Structure and Function: Organelles, Membrane and Cell Types
Cell structure and function: cell theory, prokaryotic and eukaryotic cells, the plasma membrane, cell organelles, and how plant and animal cells differ.
UPSC GS 4 Syllabus: Ethics, Integrity and Aptitude Explained
The full UPSC GS 4 syllabus for the ethics paper, what it has actually asked from 2019 to 2026, how case studies are marked, and how…
UPSC Essay Topics Previous Years: Every Topic From 2007 to 2026
UPSC essay topics previous years list: all 138 topics from 2007 to 2026, year by year and by theme, how the topics have changed and which…
UPSC Essay Paper: Syllabus, Pattern and How to Write the Essay
The UPSC essay paper explained: official syllabus, pattern and marks, the 2025 and 2026 topics, and how to write and prepare the essay for UPSC Mains.
UPSC GS 3 Syllabus: Economy, Agriculture, Science, Environment and Security
The UPSC GS 3 syllabus for Mains in full: economy, agriculture, science, environment, disasters and security, with topic-wise weightage from 285 PYQs.
UPSC GS 2 Syllabus: Polity, Governance, Social Justice and International Relations
The UPSC GS 2 syllabus for Mains in full: polity, governance, social justice and international relations, with topic-wise weightage from 285 PYQs.
UPSC GS 1 Syllabus: History, Culture, Geography and Indian Society
The UPSC GS 1 syllabus for Mains in full: Indian culture, modern and world history, Indian society and geography, with weightage from 294 PYQs.
UPSC CSAT Syllabus: Topics, Qualifying Marks and What the Paper Asks
The UPSC CSAT syllabus in full: what CSAT is, the maths, reasoning and comprehension topics, the 33 per cent qualifying marks and weightage since 2011.
UPSC Prelims Syllabus: Seven Subjects of GS Paper 1 and Their Weightage
The UPSC Prelims syllabus in full: the seven subjects of GS Paper 1, weightage from 1,500 past questions, the most important topics and the 2027 dates.
UPSC Syllabus 2027: Prelims, CSAT, Mains and Official PDF
The full UPSC syllabus for Prelims, CSAT and Mains: the official text of every General Studies paper, the official PDF, and how often each topic is…
UPSC Exam Pattern: Prelims, Mains and Interview Marks
UPSC exam pattern: Prelims 400 marks with one-third negative marking, Mains 1,750 marks in nine papers, interview 275 marks, and the official cut-offs.
UPSC Age Limit and Number of Attempts: Category-wise Rules
UPSC age limit is 21 to 32 years with category-wise relaxation. See attempts for General, OBC, SC, ST and PwBD, and what UPSC data shows on…
Polity Powers of the Governor: Executive, Legislative, Ordinance, Assent and Discretion
Powers of the Governor for UPSC: appointments, Assembly sessions, assent under Article 200, ordinances, pardons, discretion, floor tests and 2025 rulings.
Polity Governor of a State: Appointment, Qualifications, Tenure, Removal and Special Duties
Governor of a State: who appoints the Governor, qualifications, salary, oath, tenure under Article 156, removal after B. P. Singhal and special duties.
Polity Union Council of Ministers: Cabinet, Collective Responsibility and the Attorney-General
Council of Ministers for UPSC: ranks, the 15 per cent cap, Cabinet committees, collective responsibility, parliamentary control and the Attorney-General.
Polity Prime Minister of India: Appointment, Powers, Role and Relationship With the President
Prime Minister of India for UPSC: appointment under Article 75, Article 78 duties, powers, PMO and Cabinet Secretariat, confidence votes and past papers.
Polity Vice-President of India: Election, Rajya Sabha Chairmanship, Acting President and Removal
Vice-President of India for UPSC: election by both Houses of Parliament, Rajya Sabha Chairman's powers, acting President, removal and the 2025 poll.
Polity Ordinance, Pardon and Emergency Powers of the President: Articles 123, 72, 352 to 360
Emergency powers of the president for UPSC: Articles 352, 356 and 360, ordinances under Article 123 and the pardoning power under Article 72.
Polity Powers of the President of India: Executive, Legislative, Assent and Veto
Powers of the President of India for UPSC: Article 74 advice, appointments, sessions, assent and veto types, Article 143 and the 2025 opinion.
Polity President of India: Election, Qualifications, Term and Impeachment (Articles 52 to 62)
President of India for UPSC: electoral college, value of votes, qualifications, term, vacancy, impeachment under Article 61, and India versus France.
Polity Federal Features of the Indian Constitution: Parliamentary System, Courts and Rights
Federal features of the Indian Constitution for UPSC: strong Centre, cooperative federalism, parliamentary system, integrated judiciary, rights, emergency.
Polity Salient Features of the Indian Constitution: Sources, Amendment and Basic Structure
Salient features of the Indian Constitution for UPSC: length, twelve Schedules, sources by country, Article 368 amendment routes and basic structure.
Polity Constituent Assembly of India: Composition, Committees and Making of the Constitution
Constituent Assembly of India for UPSC: Cabinet Mission plan, 389 seats, committees and chairs, Drafting Committee, adoption in 1949 and the 1935 Act.
Polity Preamble to the Indian Constitution: Ideals, 42nd Amendment and Court Rulings
Preamble to the Indian Constitution for UPSC: text, five words on the State, four ideals, the 42nd Amendment, Kesavananda and the 2024 ruling.
Polity Fundamental Duties of the Indian Constitution: List of 11 Duties Under Article 51A
Fundamental Duties of the Indian Constitution: the 11 duties in Article 51A, the 42nd and 86th Amendments, the Verma Committee, laws and court rulings.
Polity Directive Principles of State Policy: Articles 36 to 51, Amendments and UCC
Directive Principles for UPSC: Articles 36 to 51, Article 37, amendments, Fundamental Rights conflict, Article 31C, Article 39(b) and uniform civil code.
Polity Citizenship in India: Articles 5 to 11, Citizenship Act, CAA and OCI
Citizenship in India for UPSC: Articles 5 to 11, the Citizenship Act 1955, modes of acquisition and loss, Section 6A, the CAA 2019 and OCI rules.
Current Affairs EOS-05 and GSLV-F17: India’s First Geosynchronous Imaging Satellite
ISRO launched EOS-05 on GSLV-F17 on 4 September 2026, India's first imaging satellite in geosynchronous orbit, after a pause of nearly eight months.
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