The book "What is non-standard analysis" by author B. A. Ouspensky is a fascinating and deep dive into the world of mathematical concepts, which may be a discovery even for experienced professionals. This work is not just a textbook, but a real intellectual odyssey that invites the reader to explore non-standard approaches to analysis and mathematics in general. In. A. Ouspensky, a well-known Russian mathematician and popularizer of science, in his book offers a unique look at traditional methods of analysis, expanding the boundaries of conventional understanding. Non-standard analysis is not just a set of new formulas and theorems, it is a whole philosophy that allows you to look at mathematics from a different angle. The author explains how non-standard methods can be applied in various fields, from physics to economics, and how they can change our perception of reality. The book will be interesting to both students and teachers, as well as to anyone who is fond of mathematics and wants to deepen their knowledge. If you are looking for new ideas for scientific research or just want to expand your horizons, “What is non-standard analysis” will be a real find for you. It is suitable for both young scientists and experienced researchers seeking new discoveries in their field. The topics raised in the book cover a wide range of issues: from the basics of non-standard analysis to its application to real-world problems. Ouspensky is not afraid to question well-established dogmas and invites the reader to think about how non-standard approaches can lead to new solutions. He shows that mathematics is not only a strict rules and formulas, but also a creative process that requires courage and non-standard thinking. The author's style is clear and accessible, which makes complex concepts understandable even for those who are not professional mathematicians. Ouspensky masterfully combines theory with practical examples, which allows the reader not only to assimilate the material, but also to apply it in practice. His previous works, such as "Mathematics and Philosophy" and "New Horizons in Mathematics", also demonstrate his ability to explain complex ideas in simple language, making him one of the most sought-after authors in the field of scientific literature. “What is non-standard analysis” is not just a book, but a challenge to your intelligence. It makes us think about how we perceive the world and what tools we use to analyze it. If you want to learn more about how non-standard analysis can change your approach to mathematics and science in general, this book will be your faithful companion on this fascinating journey. Thus, if you are looking for literature that not only expands the horizons, but also inspires new discoveries, "What is non-standard analysis" A. Uspensky is exactly what you need. Do not miss the opportunity to immerse yourself in the world of non-standard ideas and discover new horizons in mathematics!