Learn about kinks and domain walls in this physics lecture from the International Centre for Theoretical Sciences' program on gravitational waves and beyond standard model physics. Explore fundamental concepts of topological defects as part of a comprehensive workshop examining gravitational wave sources, including cosmic strings and domain walls. Delve into how these phenomena contribute to Stochastic Gravitational Wave Background (SGWB) signals and their implications for probing high-scale physics beyond the Standard Model. Gain insights from expert physicist Tanmay Vachaspati in this 76-minute presentation, which serves as the first lecture in a series covering theoretical physics concepts relevant to both particle physics and cosmology.