This chapter builds the foundation required to understand the rest of Science and Technology for UPSC. It covers the evolution of science, major scientists and engineers, India’s scientific development, important institutions, government policies and the broader challenges facing India’s science and innovation ecosystem.

Understanding these foundations also helps explain how scientific research is converted into technological capability, public policy and national development.

Once the institutional and scientific foundations are clear, India’s space programme provides one of the best examples of how research, engineering and public policy combine to create strategic and developmental capabilities.

Space technology combines scientific principles with applications in communication, navigation, weather forecasting, remote sensing, disaster management and national security. This chapter covers everything from orbits, satellites and propulsion systems to ISRO launch vehicles, exploration missions, human spaceflight and planetary science.

It also examines the growing commercial space economy, international cooperation, space security, governance and sustainability—areas that are increasingly relevant for UPSC current affairs.

While space technology allows us to observe and understand the Earth from above, biotechnology works at the cellular and molecular level to address challenges in agriculture, healthcare and the environment.

Biotechnology applies biological processes and scientific techniques to areas such as agriculture, healthcare and environmental management. This chapter begins with the fundamentals of biotechnology before examining how these technologies are used to improve crops, develop medical treatments and address environmental challenges.

For UPSC, biotechnology is particularly important because scientific innovation in this field often intersects with food security, public health, regulation, ethics and environmental concerns.

This chapter explains the scientific principles behind nuclear energy along with their practical and strategic applications. It covers the fundamentals of nuclear technology, the development of nuclear energy in India and the international institutions and frameworks governing the peaceful use of nuclear technology.

Nuclear technology is closely connected with energy security, climate policy, strategic affairs, international relations and technological self-reliance, making it a multidimensional topic for UPSC preparation.

Like nuclear infrastructure, digital infrastructure has become strategically important for a modern state, making technological capability, regulation and security increasingly interconnected.

Digital technologies increasingly influence how economies function, governments deliver services and citizens communicate. This chapter covers the foundations of ICT, communication networks, mobile technologies, the internet, India’s digital infrastructure and digital payments, before moving into artificial intelligence, generative AI, specialised chips and emerging digital applications.

It also examines the governance challenges created by these technologies, including cybersecurity, deepfakes, data privacy, data localisation and digital ethics. These topics connect technology directly with governance, internal security, the economy and individual rights.

The distinction between civilian and strategic technology is also becoming less clear, as artificial intelligence, communication networks, computing and cybersecurity increasingly influence modern defence systems.

Modern defence increasingly depends on advanced scientific and technological capabilities. This chapter introduces important technologies associated with missiles, air defence, naval systems, nuclear defence and explosives, while helping students understand the scientific principles underlying modern military systems.

For UPSC, defence technology is especially relevant when studied alongside India’s efforts towards indigenous defence production, strategic autonomy, national security and technological modernisation.

Many next-generation defence and civilian applications will depend on technologies such as robotics, quantum computing, nanotechnology and advanced materials, making emerging technologies an important bridge between present capabilities and future innovation.

This chapter focuses on technologies that could significantly transform industry, communication, computing, healthcare, defence and everyday life in the coming decades. Topics include nanotechnology, robotics, cryptography, quantum technology, advanced materials and other emerging technologies.

These subjects are particularly important for UPSC because new scientific developments frequently enter the examination through current affairs before becoming part of conventional textbooks.

Several important Science and Technology themes cut across multiple disciplines and therefore require separate attention. This chapter brings together topics such as energy technologies, intellectual property rights, medical therapeutics, particle physics and recent advances in astronomy.

Together, these areas help complete the broader Science and Technology framework and provide useful background for understanding important scientific developments reported in current affairs.