According to the author, genetics is an easy science with a very difficult language, which inevitably creates comprehension problems. To address, at least partially, this problem for non-biologists, Kitsos Louis decided to describe "in simple words" what genetics is and what it does, recording simple stories in which this particular science had (and has) a leading role. These stories explain human diseases, develop the close relationship of friendship between humans and dogs, and take us from prehistoric times to the latest achievements of science, including the genetic basis of evolution. Although it indicates where there are unsolvable bioethical problems, the author avoids taking a position, preferring to leave this to the judgment of the reader. No previous "apprenticeship" in biology is required to understand the book. Doctors and scientists may have a slight advantage, but all others - lawyers, theologians, philologists, philosophers, and, in short, those interested in learning what genetics is, whether or not they have university studies - will understand each of these genetic stories without any problem.