Relativity is a groundbreaking work that introduces readers to the complex and fascinating world of theoretical physics. In this book, Einstein explains his theory of relativity, which revolutionised our understanding of space, time, and gravity. The theory is divided into two parts: Special Relativity and General Relativity. Special Relativity addresses the relationship between space and time, introducing the famous equation E=mc². General Relativity expands on this by explaining how gravity is not just a force but a curvature of space-time caused by mass. Einstein's clear and concise writing makes these profound concepts accessible to both scientists and curious readers alike, offering a glimpse into the mind of one of the greatest physicists of all time.