Since their discovery hundreds of years ago, people have been fascinated by the properties of Fibonacci numbers. Being of mathematical significance in their own right, Fibonacci numbers have had an impact on areas like art and architecture and their traces can be found in nature and even the behaviour of the stock market. Starting with the basic properties of Fibonacci numbers, the book explores their relevance in number theory, the theory of continued fractions, geometry and approximation theory. Rather than giving a complete account of the subject, a few chosen examples are treated exhaustively. They not only reveal the bearing of Fibonacci numbers on mathematics but also provide very readable marvels of mathematical reasoning. This book is the translation of the 6th Russian edition (the first edition appeared in the early fifties and became a standard source of information on the subject). The prerequisites for reading this book are minimal. A certain acquaintance with elementary operations and a readiness for mathematical thought are enough to follow the presentation.
Apart from anybody interested in the Fibonacci number as such, the book can be used for undergraduate courses on this subject, touching on several mathematical areas on the way.