Explore the fundamental concepts of Koszul duality in this comprehensive lecture delivered by Vladimir Dotsenko from the University of Strasbourg. Delve into the first part of an in-depth introduction to this important mathematical topic, gaining valuable insights from a renowned expert in the field. Over the course of 53 minutes, discover the key principles and applications of Koszul duality, laying a solid foundation for further study and research in this area of mathematics.