It is known that a person is initially inclined to believe what he is told, especially if authoritative people tell him this. But authority does not mean that it is the ultimate truth. Many people make mistakes. And it’s not their fault or even their problem. Pushkin also wrote: “Oh, it’s not difficult to deceive me, I’m glad to be deceived myself.” The author of the book tried to argue and dispel, on the basis of facts, some seemingly indisputable truths hammered into heads from school and in student classrooms. The book consists of two parts. One is dedicated to the actual misconceptions that humanity has been “fed” for centuries, the second to falsifications. Since this book is written in the form of a dictionary, the division into two parts is arbitrary. But it will not be difficult for the reader to understand where we are talking about error and where about falsification. Some of them were done unconsciously, so to speak, the people who made them were used “in the dark,” but most pursued a specific goal - profit. Material, which happened more often, or political gain.