When defining the essence of the book in book science, the functions of the book are considered. It is necessary to note that in the course of time (at change of the approach to definition of concept "book") the list of allocated functions of the book changed, experts-book experts allocated various functions as the basic.
- In the Soviet book science the leading position was taken by the functional approach both at definition of concept "book", and at studying of functions of the book. The main representatives of this approach - I.E. Barenbaum and A.I. Barsuk - singled out the ideological function of the book as the main one. I.E. Barenbaum noted that this function not only supports the book in public use, but also forms and transforms the book as a work of writing and printing. Thus, the ideological content of the work comes to the fore [1, p. 26].
Barenbaum and Barsuk considered the communication function of I.E. and A.I. Barsuk (book as a means of information transfer) to be a universal one. The cognitive function is inextricably linked to it, but it is more related to the educational, reference, scientific and production book.
These researchers also emphasized the aesthetic and ethical functions. The aesthetic function of the book is that the book as a material and spiritual value influences its external and internal form on the reader. When performing an ethical function, the book influences the reader's feelings, disciplines the personality in a certain way, influences its behavior, i.e. acts as a moral value educator.
The same positions as I.E. Barenbaum and A.I. Barsuk are held by Malikhin. For him, the main side of the book is the content. The main function of the book is in the moral and ideological upbringing of the personality, and the book can perform this function first of all by its ideological inner content [9, p. 156].
A.M. Ioffe, when considering the functions of the book, proceeds from the fact that the book is first of all a social phenomenon; it means that the essence of the book is realized in its social functions. It also defines the function as applied to book science - "the role performed by the book concerning the needs of society or the interests of its (society's) constituent classes, social groups and individuals". [7, c. 36].
The role of the book in society is ambiguous, as it has different social functions. The book is a tool for scientific, technical and cultural progress, a source of knowledge and education, a tool for social struggle. The book acts both as an ideological and aesthetic value and as a material value, as the most important subject of spiritual consumption, the importance of which increases with the development of society, the growth of its socio-economic, political, cultural, scientific and technological level. Hence, the book is multifunctional.
A.M. Ioffe, in defining the functions of the book, notes that the book was created in response to the need of society to consolidate, preserve, transmit information, and reproduce it in order to master the experience, knowledge and ideas. Thus, from the very beginning, the book acts primarily as a source of social information, a means of transmitting information and developing knowledge accumulated by humanity [7, p. 37].
In this regard, Ioffe singles out the following functions as universal, internal functions of the book, which are inherent to its nature:
1) information - the embodiment and consolidation of semantic information in the text;
2) communicative - transfer (dissemination) of information in time and space and establishment on this basis of intellectual connections and communication between individual members of society and social groups;
3) cumulative - accumulation, concentration, preservation, organization into a certain system of spiritual values;
4) Reproduction - reproduction, recreation of accumulated information.
But among the most important functions of the book A.M. Ioffe singles out the ideological function of the book, which consists in the formation of the ideology of a certain class and the ideological impact on other classes or society as a whole. The book's ideological function is closely related to the value-oriented function - the formation of value structures of individuals and society. Also, A.M. Ioffe considers the book's agitation-propaganda, organizational, cognitive, educational, educational, aesthetic, ethical, hedonistic to be the main social functions [7, p. 37].
- An important conclusion in the work of A.M. Ioffe is that in the process of historical development of the book there is an expansion of its functions and their differentiation [7, p. 37]. Depending on the specific historical conditions, some of them may be highlighted and become dominant or secondary in importance. In general, when selecting these or those functions, it is necessary to take into account that the book influences the reader with the whole set of interrelated and interacting functions.