Explore the fascinating world of active matter in this comprehensive lecture by Sriram Ramaswamy, part of the INFOSYS-ICTS Chandrasekhar Lectures series. Delve into the study of matter whose constituents, known as active particles, convert energy into work. Gain insights into recent developments and key earlier work in the field of soft-matter and nonequilibrium physics. Learn about the collective behavior of objects like motile organisms that transform local energy input into autonomous motion. Discover the broad applications and implications of active matter research across various scientific disciplines. Benefit from the expertise of Sriram Ramaswamy, a renowned theoretician with extensive experience in nonequilibrium, soft matter, and biological physics, as he introduces this dominating presence in the landscape of modern physics.