The Computer Networks . Information security and information preservation: a training manual by B. A. Ganji is an indispensable resource for students, teachers and information technology professionals. With the rapid development of digital technologies and an increase in the number of cyber threats, this manual is becoming relevant and necessary for everyone who wants to better understand the principles of computer networks and methods of information protection. The book focuses on key aspects of computer networks and information security. The author, with extensive experience in this field, shares his knowledge on how to design and manage networks correctly, as well as how to protect them from external and internal threats. Ganja considers not only theoretical foundations, but also practical aspects, which makes the manual especially valuable for those who want to apply the acquired knowledge in real practice. The book covers a wide range of topics: from the basics of network architecture and data transfer protocols to modern methods of encryption and information protection. In. A. Ganja pays attention not only to technical aspects, but also to organizational measures that are necessary to ensure security in information systems. The reader will be able to learn about different types of threats, such as viruses, hacker attacks and data leaks, as well as how to prevent and respond to incidents. This manual will be of particular interest to students and graduate students studying information technology, cybersecurity and related disciplines. The book will also be useful to practitioners working in the field of IT, system administrators and anyone who wants to improve their skills in the field of information security. Due to its accessible language and clear structure, the material is easy to digest, making it ideal for self-study. The topics raised in the book are relevant to both educational institutions and businesses, where data protection is becoming a priority. In the face of constant cybersecurity threats, knowledge of the basics of information security and computer network management is becoming a necessary skill for any modern specialist. Ganja emphasizes the importance of creating an integrated security system that includes both technical and organizational measures. The author's style is distinguished by clarity and logical presentation, which allows the reader to easily follow the thought and assimilate complex concepts. In. A. Ganja is a well-known specialist in the field of information technology, and his work is respected among professionals. He is also the author of other tutorials and articles that highlight various aspects of computer technology and its applications. The Computer Networks . Information security and information preservation” will be a valuable addition to the library of everyone who is interested in modern technologies and wants to be aware of the latest trends in cybersecurity. This is not just a tutorial, but a whole guide to the world of information technology, which will help the reader not only to understand the theory, but also to gain the practical skills necessary for a successful career in this dynamically developing field. If you are looking for materials on cybersecurity, computer networks or information technology, this guide will become your reliable assistant and source of knowledge. Do not miss the opportunity to deepen your knowledge and prepare for the challenges posed by the modern digital world!