Embark on a lightspeed tour of fascinating celestial giants in this 38-minute lecture by Professor Amélie Saintonge. Explore the nature of black holes, their formation process, and their colossal features. Discover how these massively heavy objects possess gravity so strong that even light cannot escape. Learn about the energy released when black holes collide, creating ripples in spacetime. Delve into the challenges of observing black holes directly with telescopes. Gain insights into star mechanics, black hole sizes, formation theories, and open questions in the field. Investigate the evidence for black holes, methods of detection, and the existence of supermassive black holes. Uncover the mechanics governing these mysterious cosmic entities and their role in galactic evolution.