The article is a review of the book “What is Digital History?” by Salmi H. which discusses digital history, a new field in history, and defines its framework. The review considers a range of issues related to digital sources, their typology, approaches to the formation of the source base and their criticism. The article analyzes the author’s attitude to digitized historical sources based on original analogous sources and born-digital ones as well as methods of their processing used by contemporary historians. These aspects have a direct impact on present day historical research and must be taken into account by historians. The review also addresses the author's views on epistemology and hermeneutics which are increasingly important in the digital age. The topics named are unevenly distributed in the book. Sources of a new type are considered in detail in the chapter “The Digital Past: Sources and Problems”. Other issues are studied in the rest of chapters and in less detail. The review is complemented with examples of other projects and modern publications that were not included in the text of the reviewed book, but are essential for the topic as a whole.