The ABC of Relativity clearly and engagingly explains Einstein's Theory of Relativity to the layperson. It is considered to be a significant contribution to the popularization of science. Its author, Bertrand Russell, was an acclaimed British mathematician, philosopher and logician. Please note that in a few of the chapters, diagrams are included which clarify the author's discourse. The listener may wish to consult a published text to refer to these diagrams. (Summary by Ciiufi Galeazzi)