This book is intended for the reader whose imagination has been captured by reading a popular account about the plate tectonics and would like to know more. It concentrates on the quantitative side of the plate tectonics because most scientifically literate people are already familiar with the quantitative side.The book will enable the reader to answer questions like the following: How fast is London moving away from New York? How fast was Los Angeles moving toward San Francisco 50 million years ago? How are the motions of the plates described in mathematical terms? What geophysical observations are used to determine plate motions? How are earthquakes related to plates motions? And what drives the plates?The guiding philosophy of this book is that in plate tectonics, as in chess, more insight comes from playing the game than from talking or reading about it. This is a hands-on, how-to-do-it book. Most students find that through learning the nuts and bolts of plate tectonics, they gain new insight into its power and limitations.