UPSC Prelims Notes 2025 – Subject-Wise GS Paper 1 & CSAT Paper 2 Notes

Download expert-curated UPSC Prelims Notes for GS Paper 1 & CSAT Paper 2. Covering Polity, History, Geography, Economy & more. Aligned with latest UPSC syllabus

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Agriculture
Art & Culture
Constitution
Disaster Management
Economic Development
Environment
Ethics, Integrity & Aptitude
Geography
Governance
Indian Society
International Relations
Modern Indian History
Polity
Science & Technology
Security
Social Justice
World History

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UPSC Prelims Notes – Complete Subject-wise Notes for GS Paper 1 & CSAT Paper 2 

Preparation for UPSC Civil Services Preliminary Examination is all about strategic planning, concise resources, and intelligent revision. With lakhs of candidates appearing annually and only a few thousand making it through Prelims, having access to well-structured UPSC Prelims Notes is absolutely essential. Whether you are a beginner or an old contestant, this page provides you with good-quality, topic-based UPSC Prelims Notes for both GS Paper 1 and CSAT Paper 2, prepared by experts and based on the current UPSC trend. 

Our UPSC Prelims Notes are crafted after detailed analysis of the official syllabus, previous year questions (PYQs), and recent affairs—giving you nothing but the essentials. These UPSC Prelims Notes, expert-created, save time, enhance conceptual clarity, and enhance retention. Use these UPSC Prelims Notes as your go-to companion on the journey to crack India's most difficult exam.

Subject

Key Focus Areas

Agriculture

Cropping patterns, agricultural reforms, MSP, irrigation, allied activities

Art & Culture

Architecture, dance, music, painting, cultural institutions, UNESCO sites

Constitution

Preamble, Features, Fundamental Rights/Duties, DPSPs, Amendments

Disaster Management

Disaster types, NDMA guidelines, risk reduction, disaster resilience

Economic Development

GDP, inflation, banking, monetary/fiscal policy, Budget, economic surveys

Environment

Biodiversity, conservation, environmental laws, climate change

Ethics, Integrity & Aptitude

Ethics theory, case studies, integrity, moral thinkers, public administration ethics

Geography

Physical, Indian and World geography, maps, natural resources, climatic patterns

Governance

E-governance, transparency, accountability, citizen charters

Indian Society

Diversity, social issues (caste, gender), communalism, secularism

International Relations

Bilateral & multilateral relations, regional groupings, global institutions

Modern Indian History

Revolt of 1857, freedom struggle, Gandhian era, important events & personalities

Polity

Union & State governments, Judiciary, local bodies, constitutional bodies

Science & Technology

ISRO missions, innovations, biotechnology, IT, health tech, defense tech

Security

Internal security, cyber security, border management, terrorism

Social Justice

Welfare schemes, vulnerable sections, education, health, NGOs

World History

French, American, Russian Revolutions, World Wars, colonization & decolonization

UPSC Prelims Examination Overview

The UPSC Prelims Examination is the initial and most competitive phase of the Civil Services Examination held by the Union Public Service Commission. It is a screening examination for the Mains phase and is divided into two objective-type papers held on the same day:

Paper

Type

Number of Questions

Total Marks

Duration

Additional Information

General Studies Paper 1

Objective Type

100 questions

200 marks

2 hours

Score counted for merit ranking in Prelims

CSAT – General Studies Paper 2

Objective Type

80 questions

200 marks

2 hours

Qualifying in nature (minimum 33% or 66 marks required)

Key Features of UPSC Prelims

  • Negative Marking: 1/3rd marks are reduced for each incorrect response in both papers
  • Qualifying Nature of CSAT: Marks from GS Paper 1 alone are taken for Prelims merit list; candidate needs to just qualify CSAT
  • Medium: Both papers are given in English and Hindi
  • Nature: Objective and OMR-based (offline mode)

Why Use Our UPSC Prelims Notes?

  • UPSC Prelims Notes made by experienced faculty members having years of guidance experience for aspirants.
  • Updated according to the most recent UPSC pattern and Previous Year Questions (PYQs), so that your preparation remains in harmony with the latest trends.
  • To-the-point, concise, and exam-focused UPSC Prelims Notes that will assist you in prioritizing what matters the most for the exam.
  • Perfect for revision as well as first-time study, our UPSC Prelims Notes suit all levels of your preparation.
  • Available to download in PDF format for handy offline use, so it's easy to study and revise your UPSC Prelims Notes at your own pace, anywhere, anytime.

UPSC Prelims GS Paper 1 Notes – Subject-Wise Detailed Coverage

The UPSC Prelims GS Paper 1 Notes offer detailed coverage of a broad array of topics relevant to the exam. Topics covered range from Polity, History, Geography, Economy, Environment, Science & Technology, and Current Affairs. The following is the entire list of subjects and important topics covered in the UPSC Prelims GS Paper 1 Notes that will assist you in effectively covering each section:

Subject

Key Topics

Polity and Governance

Constitution of India: Features, Preamble, Schedules

Fundamental Rights & Duties, DPSPs

Union and State Government: President, PM, Parliament, Governor, CM

Constitutional & Non-Constitutional Bodies

Judiciary: Supreme Court, High Courts, Judicial Review

Recent Government Schemes & Policies

Panchayati Raj & Local Governance

Indian History – Ancient, Medieval, Modern

Ancient History: Indus Valley Civilization

Vedic Period, Mahajanapadas, Buddhism & Jainism

Maurya and Gupta Empires

Medieval History: Delhi Sultanate

Mughal Empire

Bhakti and Sufi Movements

Modern History: British Expansion, Revolt of 1857

Freedom Movement: Moderates, Extremists, Gandhi Era

Important Acts, Committees, INC Sessions

Art and Culture

Indian Classical & Folk Dances

Music and Painting Styles

Temple Architecture

UNESCO World Heritage Sites

Cultural Institutions (Sangeet Natak Akademi, ASI)

Geography

Physical Geography: Landforms, Climatology, Oceanography

Indian Geography: Rivers, Mountains, Soils, Forests

Economic Geography: Minerals, Industries, Agriculture

World Geography and Map-based Questions

Economy

Basic Concepts: GDP, Inflation, Fiscal Deficit

Budget and Economic Survey

Monetary Policy, Banking System, RBI Functions

Agriculture and Industry Sector

Current Affairs related to Economy

Environment & Ecology

Ecosystems and Biodiversity

Climate Change and Global Warming

Environmental Treaties (CBD, UNFCCC, Paris Agreement)

Wildlife Protection Acts and Institutions

Species in News and Conservation Projects

Science & Technology

Space Missions (ISRO), Nuclear & Defence Tech

Biotechnology, Health, and Nanotechnology

Recent Developments in Digital Tech & AI

Disease Outbreaks and Vaccines

Society & Social Justice

Social Issues: Poverty, Caste, Gender, Religion

Education & Health Initiatives

Government Welfare Schemes for Vulnerable Groups

Role of NGOs, SHGs, Civil Society

International Relations (IR)

India’s Bilateral Relations

International Organizations (UN, WTO, WHO, IMF)

Neighbourhood First Policy

India’s Global Groupings (BRICS, QUAD, SCO)

Important Treaties and Summits

UPSC CSAT Paper 2 Notes – Reasoning, Aptitude & Comprehension

Although CSAT Paper 2 is qualifying in character, it has turned out to be more and more unpredictable over the past few years. Strong knowledge of reasoning, reading, and elementary mathematics is required to clear this paper. The changing trend requires the candidates to sharpen their skills in:

Topic

Subtopics

Quantitative Aptitude

Number System

LCM, HCF

Profit-Loss, Time-Speed-Distance

Averages, Speed, Time, Distance, Profit, and Loss

Data Interpretation (DI)

Graphs, Tables, Pie Charts, Bar Diagrams

Probability, Permutation & Combination

Basic Probability, Permutation and Combination Calculations

Logical & Analytical Reasoning

Blood Relations

Understanding Relationships and solving puzzles related to family relationships

Seating Arrangement

Linear, Circular Arrangements, Puzzle Solving

Coding-Decoding

Identifying Patterns, Letters, and Number Codes

Puzzle Solving

Analytical Reasoning Problems involving Shapes, Numbers, etc.

Syllogisms and Venn Diagrams

Logical Deduction, Venn Diagram Representation

Input-Output and Analytical Puzzles

Logical Patterns, Number Series, Arrangement, and Inferences

Reading Comprehension

Short & Long Passages

Reading, Understanding, and Analyzing Passages

Direct & Inferential Questions

Answering based on facts or inferred information

Elimination Technique Practice

Identifying irrelevant information and eliminating options effectively

Decision-Making & Problem Solving

Case Studies with Ethical Dilemmas

Analyzing and solving ethical case studies, decision-making frameworks

Practical Judgement Questions

Problem-solving with realistic scenarios, drawing conclusions based on practicality

How to Use These UPSC Prelims Notes Strategically?

  • Start with NCERTs: Build a solid foundation by beginning with NCERTs, which provide the fundamentals. Once you are familiar with those, move on to these UPSC Prelims Notes for brief, exam-oriented material. 
  • Download and Organize: Download our UPSC Prelims Notes in PDF format and place them subject-wise in folders on your computer or smartphone. This will make it easy to access the right material while revising.
  • Revise Multiple Times: Keep revising the notes multiple times prior to the Prelims exam. Regular revision is the key to maintaining critical information and being well-prepared for the exam.
  • Link Static Notes with Current Affairs: Keep yourself updated by relating static concepts from the notes with current affairs. Utilize monthly magazines or newspapers in order to relate your UPSC Prelims Notes with recent developments.
  • Regular Practice of CSAT: For CSAT Paper 2, practice 30-40 minutes daily. Use our CSAT notes and mock questions to increase problem-solving capabilities and accuracy.

Conclusion

Cracking UPSC Prelims requires intelligent study, not hard work. Our subject-wise UPSC Prelims Notes for GS Paper 1 and CSAT Paper 2 are carefully designed to organize your prep and cut down on information overload. From mastering mainstream static topics to honing your aptitude and comprehension skills for CSAT, these notes serve as your one-stop resource for effective and efficient revision.
Download, revise, and stay ahead with our UPSC Prelims Notes 2025 – Your success starts here.

FAQs on UPSC Prelims Notes 2025 – Subject-Wise GS Paper 1 & CSAT Paper 2 Notes

These notes are designed to cover all must-know areas for Prelims. Combine them with PYQs, test series, and regular current affairs for the best results.

Currently, the notes are available in English. Hindi versions are under development.

Yes, each subject section has a direct link to download the latest PDF version.

We update all UPSC Prelims Notes regularly in sync with the evolving exam trend and current affairs.

These notes are brief, exam-oriented, and derived from the recent UPSC trends and PYQ analysis. They cut through the waste and enable you to concentrate only on what's required to clear Prelims.

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Best IAS Coaching In Delhi, UPSC Online & Offline Classes by IAShub

Are you dreaming of becoming an IAS officer? Then, IAShub can be your best guide. It is one of the Best IAS Coaching in Delhi. Many students who want to clear the UPSC exam join IAShub for learning. The institute gives both online and offline classes. Their teachers are experienced and helpful. They easily explain every topic. Students also get notes, tests, and tips to do well in the exam.

UPSC Online Classes by IAShub

IAShub is in Delhi and is trusted by many UPSC students. It offers coaching for every part of the UPSC exam – Prelims, Mains, and Interview. The classes are simple and easy to understand. The teachers are experts and guide students in the right way. IAShub is also known for its helpful notes, test series, and answer-writing practice. IAShub is the best coaching in Delhi and also gives UPSC Online Classes. This helps students from any place in India to learn. The online classes are live and also recorded. So, students can watch them anytime. These classes cover the full UPSC syllabus.

Key Offerings Provided by IAShub

Here are some important services provided by IAShub:

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  • Live Classes: Students who live far can join live UPSC online classes. These classes are just like real classes.
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UPSC Exam Overview

The UPSC Civil Services Exam has three parts:

  • Prelims: It has two papers: General Studies and CSAT.
  • Mains: It has nine papers, including essays and optional subjects.
  • Interview: It tests the personality and confidence of the student.

This exam is tough, but with the right guidance, it becomes easy to manage. Students must study smart and stay regular.

How IAShub Helps in the UPSC Journey

IAShub supports students from the beginning to the end. It gives the right books, tests, and notes. The classes are easy to follow, and the teachers are always ready to help. Students get personal doubt sessions too. The test series and answer checking help students learn where they need to do better. Also, free study materials save time and money.
IAShub also guides students during the final stage – the interview. Experts take mock interviews and give useful tips. This full support makes IAShub one of the best IAS coaching in Delhi.

Best IAS Coaching In Delhi FAQs

Yes, IAShub offers live and recorded online classes. Students can attend from any part of India.

Classes are available in both English and Hindi, so students can choose the language they are comfortable with.

The classroom centre is located in Delhi. Students can visit and join offline batches there.

IAShub gives interview guidance sessions to help students prepare for the final round of UPSC.