On June 26, 2000, a very significant event occurred, about which much was written in the press. At a press conference with the participation of the President of the United States and the Prime Minister of Great Britain, representatives of two research teams - the international consortium Human Genome Project and the company Celera Genomics - solemnly announced that, as a result of many years of efforts of a large number of scientists and enormous funding, the decoding of the human genome (more precisely , the complete structure of DNA has been determined). The Project of the Century, which has no analogues in scale, was successfully implemented. What has humanity learned and gained as a result of this? How does this new knowledge help a person in solving his many everyday problems? What secrets does the human genome keep? All this is discussed in this monograph, written in a popular form and intended for the widest range of readers: for high school students, school teachers, students and university teachers, and in general for all educated people who want to know more about ourselves.