This lecture introduces the course on Stellar and Galactic Dynamics, focusing on the evolution of self-gravitating systems under their own gravity. The instructor discusses the course structure, emphasizing the importance of understanding gravitational forces and potential theory. The lecture outlines the topics to be covered over the semester, including the standard model in cosmology, the physics of galaxies, and the mathematical frameworks necessary for analyzing stellar orbits and dynamics. The instructor highlights the transition of the course from the fall to the spring semester and the integration of new content from related courses. The lecture also provides insights into the instructor's background, research interests in galaxy formation and evolution, and the development of numerical tools for astrophysical simulations. The importance of collaboration with other institutions and the use of platforms like Moodle for course communication are also mentioned. Overall, this lecture sets the stage for a comprehensive exploration of the dynamics governing stellar and galactic systems.