Explore the fascinating world of circadian rhythms in this comprehensive lecture by Michael Rosbash. Delve into the history, current understanding, and future implications of these biological timekeepers. Learn about light entrainment, light-dark cycles, and their impact on various organisms from cyanobacteria to animals and plants. Discover the evolutionary aspects of circadian rhythms and the genetic foundations that led to groundbreaking research. Understand the molecular mechanisms behind the feedback loop and temporal profiles that govern these rhythms. Examine the challenges in the field, including the range of entrainment and its physiological effects. Investigate the connections between circadian rhythms and metabolism, diabetes, and sleep disorders. Gain insights into time-restricted feeding and sleep phase syndromes, and their potential implications for human health and well-being.