Encyclopedia of Elementary Mathematics . Book 4. Geometry" edited by P. C. Alexandrova is not just a textbook, but a real treasure trove of knowledge that will open before the reader the amazing world of geometry. This work, which is part of an extensive series, is intended for anyone who seeks a deeper understanding of the basics of mathematical science, regardless of their level of training. It contains key concepts, theorems and tasks that will help not only schoolchildren, but also students, as well as all lovers of mathematics who want to refresh their knowledge. Geometry is not just a set of formulas and theorems, it is a language that describes the world around us. In this book, the authors offer the reader a fascinating journey through the basics of geometry, starting with the simplest figures and ending with complex polyhedra. Each chapter is imbued with clarity and logic, which allows even those who are not specialists to easily assimilate the material. The book covers topics such as the properties of triangles, circles, polyhedra and much more, making it an ideal tool for preparing for exams or just for self-education. Who can like this book? First of all, it will be interesting for schoolchildren and students studying mathematics at the secondary school level and in universities . However, you should not limit yourself to this audience .. Puzzle lovers, parents seeking to help their children in their studies, as well as teachers looking for quality material for lessons, will find a lot of useful information in it. The book is written in an accessible language, which makes it suitable even for those who are just beginning to get acquainted with mathematics. The topics raised in the Encyclopedia of Elementary Mathematics go beyond the mere study of formulas. The authors consider geometry as an art, emphasizing its aesthetic side and connection with other sciences. For example, in the book you can find sections devoted to geometric figures in art and architecture, which makes the study more fascinating and multifaceted. It is not just a set of theoretical knowledge, but a whole world in which geometry intersects with history, culture and even philosophy. Style P. C. Alexandrova and his co-authors are distinguished by clarity and structure. They are able to explain complex things in simple language, which makes their work available to a wide audience. In the previous books of the series, this feature can also be seen - the authors seek not only to convey knowledge, but also to inspire the reader to further study mathematics. If you liked such works as "Encyclopedia of elementary mathematics . Book 1. Arithmetic" or "Encyclopedia of Elementary Mathematics . Book 2. The fourth book will not leave you indifferent. In conclusion, "Encyclopedia of Elementary Mathematics. Book 4. Geometry" is not just a textbook, but a real find for anyone who wants to deepen their knowledge in the field of mathematics. It offers the reader not only theoretical knowledge, but also practical tasks that will help to consolidate the studied . This book will become a faithful assistant in learning and will open new horizons for everyone who is ready to plunge into the fascinating world of geometry. Do not miss the opportunity to take a step towards knowledge that will help you not only in your studies, but also in your life.