The textbook is devoted to a section of science called "Digital Forensics", which describes the basic concepts, types and tasks of digital forensics, theoretical and practical foundations of computer technology and computer technology in the investigation of computer crimes and expert work. The textbook is designed for undergraduate students majoring in "Information Security" and "Cryptography and Cryptanalysis," and may also be useful to a wide range of professionals whose activities are related to information security and investigation of computer crimes.