I first encountered this series of books, written by Richard P Feynman, in my local book retailer and I was surprised at their size. Despite the nature of their subject, they are barely a couple hundred pages in length. Usually scientific books are much thicker volumes. But when one realises these books were written from notes derived for student presentations by Feynman, then size doesn't really matter. I am more inclined to purchase a 'thin' book than a 'thick' book because apart from being cheaper to buy and easier to carry, it should be an easier book to read. Doubtless, size is a marketing ploy but it means these books are affordable to a great many more people.<br><br>The information these books contain, often illustrated by original drawings by the author, help to convey some quite complex theories. These theories maybe right or they maybe wrong but they serve to illustrate the thoughts of a 'genius' whom many professionals believe rivalled Einstein in terms of his vision of how the universe works. Feynman was a controversial, colourful, some say eccentric theoretical physicist who cared little for convention and left an indelible mark in understanding science.<br><br>I purchased 3 books in this series and I purchased 3 more for a friend's birthday. Doubtless I will purchase other books in the same series when I have time to read them.