Delve into the fascinating realm of perovskites in this 2017 Bragg Lecture by Mike Glazer, Emeritus Professor at Oxford University. Explore the crystalline materials that comprise 38% of Earth's volume and their significant practical applications in electronics, ultrasonics, and thermal sensing devices. Discover how minute alterations in crystal structures lead to a vast array of properties and why perovskites are crucial in everyday life. Learn about translational symmetry, special women in the field, industrial uses, pyroelectric and piezoelectric effects, and hybrid perovskites. Gain insights into phase diagrams, intrinsic effects, and polarization rotation. This comprehensive lecture covers everything from the basics of perovskite structure to advanced concepts like MPB and PZT, providing a thorough understanding of these remarkable materials and their impact on various industries.