The Theory of Electrical Circuits . Handbook: teaching aid. At 3 p.m.. H. 1: Electrical Circuits of Constant and Variable by A. P. Kuruleva is an indispensable source of knowledge for students, graduate students and anyone interested in electrical engineering and electronics. In the first part of this volumetric manual, the author is deeply immersed in the foundations of the theory of electrical circuits, revealing to readers not only theoretical aspects, but also practical applications, which makes the book especially valuable for future engineers and specialists in the field of electrical engineering. Kurulev, known for his clear style of presentation and deep understanding of the subject, offers readers an accessible and understandable explanation of complex concepts. His experience in teaching and research allows him to effectively transfer knowledge, making this book an ideal teaching tool for both self-study and use in educational institutions. In it you will find not only theoretical foundations, but also many examples, tasks and illustrations that will help to consolidate the material and develop practical skills. The book covers a wide range of topics, ranging from the basic concepts of electrical circuits to more complex concepts related to the analysis of DC and AC circuits. The reader will be able to learn about Ohm and Kirchhoff's laws, circuit analysis methods, and various types of components such as resistors, capacitors, and inductances. Particular attention is paid to the differences between DC and AC, which is a key point for understanding the operation of modern electrical systems. This book will be interesting not only for students of technical specialties, but also for practicing engineers who want to refresh their knowledge or understand new aspects of the theory of electrical circuits. It can also be useful for teachers who are looking for quality teaching materials for their students. If you are interested in topics such as electrical engineering, electronics, circuitry, or even just want to better understand how electrical devices work in your home, then this guide will be a real find for you. Kurulev not only shares knowledge, but also inspires his readers to further study and research in the field of electrical engineering. His writing style is clear and logical, which makes it easy to digest even the most complex topics. There are many practical tasks in the book that will help the reader not only to understand the theory, but also to apply it in practice. This is especially important for those seeking a career in engineering, where theoretical knowledge needs to be underpinned by practical skills. Do not forget that the "Theory of Electrical Circuits" is only the first part of a three-volume edition. This means that more in-depth and fascinating research is ahead of the reader in the following volumes, which will be devoted to more complex aspects of the theory and practice of electrical circuits .. Thus, the book not only answers current questions, but also opens the door to new knowledge and opportunities. If you are looking for a quality electrical circuit training manual that combines theory and practice, then “Electric Circuit Theory. Guide" A. P. Curly is exactly what you need. Do not miss the chance to deepen your knowledge and become a real expert in this important field of science and technology!