The book “Open Resonators and Open Waveguides” by Lev Albertovich Weinstein is a fascinating and in-depth study in the field of physics and engineering, which immerses the reader in the world of electromagnetic waves and their applications. This publication will be a real find for students, graduate students and professionals working in the field of radio physics, electronics and optics. In his book, Weinstein examines the concepts of open resonators and waveguides, which play a key role in modern signal transmission and processing technologies. The author shares his knowledge and experience, explaining complex physical phenomena in accessible language. He not only describes the theoretical foundations, but also illustrates them with practical examples, which makes the material especially valuable for those who seek to apply the knowledge gained in practice. The book covers a wide range of topics, including the basic principles of the work of resonators and waveguides, their design features and methods of analysis. Weinstein focuses on the importance of these elements in various fields, such as radio communications, optical technology, and quantum electronics. Readers will be able to learn about the latest developments in this field, as well as the prospects for further research. "Open resonators and open waveguides" will be of interest not only to students and graduate students, but also to practicing engineers who are looking for new approaches to solving complex problems. The book could be a handbook for those working in the development and optimization of radio frequency devices, as well as for researchers seeking to deepen their knowledge in wave physics. The style of Lev Albertovich Weinstein is distinguished by the clarity and logic of the presentation He masterfully combines theory with practice, which makes his work especially valuable for readers seeking not only to understand, but also to apply the knowledge gained. Weinstein is the author of many scientific publications and teaching aids, his work is respected in scientific circles. Readers familiar with his previous editions will appreciate the consistency and depth of analysis he offers in this book. Topics raised in Open Resonators and Open Waveguides are relevant in light of the rapid development of technology. With rapid progress in the field of communication and data processing, understanding the basics of the work of resonators and waveguides becomes not only useful, but vital for specialists in this field. Weinstein’s book not only deepens knowledge, but also inspires new research and experiments. If you’re looking for literature that combines scientific rigor and practical value, Open Resonators and Open Waveguides is what you need. It will be an excellent addition to the library of anyone interested in physics, engineering and new technologies. Read, explore and discover a world where physics meets innovation and theoretical knowledge finds practical application.