"Leonardo of Pisa's Liber Abaci (Book of Calculation) is one of the most important books in the history of European mathematics. Leonardo learned his mathematics from the Islamic mathematical tradition (some have even argued that he should be considered part of that tradition), but he wrote his books in Latin. As a result, he became one of the most important mediators of that tradition to European readers ... here it is at last, the Liber Abaci...