This reference manual presents materials on industrial designs of special equipment of domestic and foreign production, designed to protect information. Information about methods for securing and monitoring information using technical means is provided in an accessible form. More than 100 schematic diagrams of information protection devices and objects are provided , the logic and operating principles of these devices are described, and recommendations for installation and configuration are given. Methods and means of protecting the information of personal computer users from unauthorized access are considered. Brief descriptions and recommendations on the use of software products and systems of limited access are given. The book is intended for a wide range of readers, trained radio amateurs who want to apply their knowledge in the field of protecting objects and information, specialists involved in ensuring the protection of information. It is of interest for familiarization with heads of government and other organizations interested in protecting commercial information.