The Dictionary explains the traditional normative spellings of Russian orthograms that do not obey any rules. Such orthograms make it difficult for writers, prompting a desire to understand the reasons for spellings that seem random and illogical. The dictionary frees from the need for cramming and mechanical memorization of difficult cases of Russian spelling, instilling a conscious attitude to the written Russian word, a desire to understand the logic of its writing and thereby helping to form stable spelling skills. The reader gets acquainted with the corresponding historical processes in the Russian language, which determined the appearance of unverifiable orthograms. The dictionary explains over 6,000 unverifiable orthograms of the Russian language.