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.
- 681 articles
- 9 subjects
- 199 current affairs
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The whole syllabus, subject by subject
Each subject page lists every article, grouped by topic area, with a search box.
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 44 articles→
GS II05
International Relations
20 articles→
GS III06
Economy
Agriculture and Allied Sectors 22 articles→
GS III07
Environment
2 articles→
GS III08
Science and Tech
33 articles→
GS IV09
Ethics
1 article→
Prelims and Mains10
Current Affairs
Explained against the syllabus, month by month 199 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 asked from 2019 to 2026, how case…
02
UPSC Essay Topics Previous Years: Every Topic From 2007 to 2026
UPSC essay topics previous years, in full: All 138 from 2007 to 2026, year by year and by theme, with…
03
UPSC Essay Paper: Syllabus, Pattern and How to Write the Essay
The UPSC essay paper explained, with the official syllabus, pattern and marks, the 2025 and 2026 topics, and how to…
04
UPSC GS 3 Syllabus: Economy, Agriculture, Science, Environment and Security
The UPSC GS 3 syllabus for Mains in full, covering economy, agriculture, science, environment, disasters and security, with weightage from…
05
UPSC GS 2 Syllabus: Polity, Governance, Social Justice and International Relations
The UPSC GS 2 syllabus for Mains in full, covering polity, governance, social justice and international relations, with weightage from…
06
UPSC GS 1 Syllabus: History, Culture, Geography and Indian Society
The UPSC GS 1 syllabus for Mains in full, covering Indian culture, modern and world history, Indian society and geography,…
07
UPSC CSAT Syllabus: Topics, Qualifying Marks and What the Paper Asks
The UPSC CSAT syllabus in full, with what CSAT is, the maths, reasoning and comprehension topics, 33 per cent qualifying…
08
UPSC Prelims Syllabus: Seven Subjects of GS Paper 1 and Their Weightage
The UPSC Prelims syllabus in full, with the seven subjects of GS Paper 1, weightage from 1,600 past questions and…
09
UPSC Syllabus 2027: Prelims, CSAT, Mains and Official PDF
The UPSC syllabus for Prelims, CSAT and Mains, with 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, full-length mocks and CSAT papers, in English and Hindi, with every option explained.
- 67tests
- 15sectional
- 17current affairs
- 20full-length
- 15CSAT
Starter Pack
₹49 Freethree complete tests
- A GS Paper I test of 100 questions on the static syllabus
- CSAT Test 1 with 80 questions
- The January 2026 current affairs test
Current Affairs Cyclone Arnab 2026: Landfall in Andhra Pradesh, Rapid Intensification and Odisha Floods
Cyclone Arnab explained: how the 2026 Bay of Bengal storm intensified, its landfall near Yanam, who named it, the Odisha floods and IMD warnings.
Polity Attorney General of India and Advocate General: Article 76, Article 165, Duties and Rights
The Attorney General of India under Article 76, with appointment, duties, rights in Parliament and limits, and the Solicitor General and Advocate General.
Science and Tech Gene Therapy and Biotechnology in Medicine: Insulin, CAR-T, RNAi and Diagnostics
Gene therapy explained: its types, recombinant insulin, biopharmaceuticals, CAR-T cell therapy, RNA interference and molecular diagnostics in India.
Science and Tech Recombinant DNA Technology: Tools, PCR, DNA Fingerprinting and CRISPR
Recombinant DNA technology explained: restriction enzymes, vectors, the steps of gene cloning, PCR, DNA fingerprinting, genome sequencing and CRISPR-Cas9.
Polity Right to Equality: Articles 14 to 18 of the Indian Constitution Explained
Right to Equality explained: Article 14 equality before law, Article 15, Article 16 and reservation, Article 17 untouchability and Article 18 on titles.
Polity Fundamental Rights of Indian Constitution: Part III, Article 12 and Article 13
Fundamental Rights of Indian Constitution: the six rights with articles, their features, Article 12 definition of State and Article 13 on void laws.
Polity Election Commission of India: Article 324, Powers, Functions and Appointment
Election Commission of India under Article 324: composition, appointment and removal of the CEC, powers and functions, Model Code of Conduct, EVMs and SIR.
Polity Comptroller and Auditor General of India (CAG): Article 148, Duties, Powers and Role
Comptroller and Auditor General of India (CAG) under Article 148: appointment, independence, duties under Articles 149 to 151, audit types and the PAC.
Polity Right Against Exploitation and Freedom of Religion: Articles 23 to 28
Right against exploitation and freedom of religion: Article 23 forced labour, Article 24 child labour, Articles 25 to 28 and Indian secularism, with PYQs.
Polity Right to Freedom: Articles 19 to 22, Article 21 and Preventive Detention
Right to Freedom explained: Article 19 freedoms and their limits, Article 20, Article 21 and the right to privacy, Article 21A and Article 22 detention.
Polity Delimitation in India and the Representation of the People Acts, 1950 and 1951
Delimitation in India: the four Delimitation Commissions, the seat freeze, the 2026 Bill and the Representation of the People Acts, 1950 and 1951.
Polity Union Public Service Commission and State PSCs: Article 315 to 323, Functions and Independence
Article 315 to 323 explained: the Union Public Service Commission and State PSCs, the UPSC chairman and members, removal, functions and independence.
Science and 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 and 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 and 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.
Physics Nuclear Fission and Fusion: Radioactivity, Half-Life and Nuclear Reactors
Nuclear fission and fusion explained: radioactivity, half-life, how a reactor works, India's nuclear power plants, the three stages and ITER.
Physics 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 and 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 and 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.
Physics 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.
Physics 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 Article 370: Union Territories of Puducherry, Jammu and Kashmir and Ladakh
Article 239A explained: Puducherry's Assembly, what Article 370 was and how it ended, the Jammu and Kashmir Reorganisation Act 2019, and Ladakh's demand.
Polity Union Territories of India: List, Map, Administration and Delhi Under Article 239AA
Union territories of India explained: list and map of all eight with capitals, Articles 239 to 241, Article 240 and Delhi under Article 239AA.
Physics 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.
Physics 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 and 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 and 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 and 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 and 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 and 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 and 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.
Prehistoric India 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.
Prehistoric India 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 and 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 and 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.
Prehistoric India Mesolithic Age in India: Microliths, Sites and Bhimbetka Rock Paintings
Mesolithic Age in India, the Middle Stone Age of 12,000 to 10,000 years ago: microliths, major sites, the Bhimbetka rock paintings and daily life.
Prehistoric India 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 three phases, stone tools, 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, with the Legal Services Authorities Act, NALSA, who gets free legal aid, Permanent and National Lok Adalats, and Gram Nyayalayas.
Science and 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 and 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, with the 25 courts, 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 and 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 and 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, with Article 131 disputes, Article 32 writs, appeals and special leave, Article 143 advice and the curative petition.
Polity Supreme Court of India: Collegium System, Appointment, Tenure and Removal of Judges
Collegium system explained, with how Supreme Court judges are appointed, their qualifications, tenure and salary, the NJAC verdict and removal.
History Delhi Sultanate: Five Dynasties, Rulers, Timeline and Map, 1206 to 1526
Delhi Sultanate (1206 to 1526): the five dynasties and their rulers, timeline and map, iqta and administration, coins, monuments and decline.
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 and 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 and 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 and 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 and 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 asked from 2019 to 2026, how case studies are marked, and how to…
UPSC Essay Topics Previous Years: Every Topic From 2007 to 2026
UPSC essay topics previous years, in full: All 138 from 2007 to 2026, year by year and by theme, with how the topics have changed and…
UPSC Essay Paper: Syllabus, Pattern and How to Write the Essay
The UPSC essay paper explained, with the official syllabus, pattern and marks, the 2025 and 2026 topics, and how to write and prepare the essay.
UPSC GS 3 Syllabus: Economy, Agriculture, Science, Environment and Security
The UPSC GS 3 syllabus for Mains in full, covering economy, agriculture, science, environment, disasters and security, with weightage from 285 PYQs.
UPSC GS 2 Syllabus: Polity, Governance, Social Justice and International Relations
The UPSC GS 2 syllabus for Mains in full, covering polity, governance, social justice and international relations, with weightage from 285 PYQs.
UPSC GS 1 Syllabus: History, Culture, Geography and Indian Society
The UPSC GS 1 syllabus for Mains in full, covering 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, with what CSAT is, the maths, reasoning and comprehension topics, 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, with the seven subjects of GS Paper 1, weightage from 1,600 past questions and the most important topics in each.
UPSC Syllabus 2027: Prelims, CSAT, Mains and Official PDF
The UPSC syllabus for Prelims, CSAT and Mains, with 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 explained, with Prelims of 400 marks and negative marking, Mains of 1,750 marks in nine papers, the 275-mark interview and the 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 explained: Executive, legislative, financial and judicial powers, assent under Article 200, ordinances and discretion.
Polity Governor of a State: Appointment, Tenure, Removal and Special Responsibilities
Who appoints the Governor of a State, the qualifications, oath and tenure under Article 156, removal after B.P. Singhal, and special responsibilities.
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.
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