Abstract: In the article the meaning of terms "information", "knowledge", "thesaurus", "ontology" with reference to the sector of informatics, which studies processes of mutual transformations of the data, information and knowledge, is specified. It allows provision of short description of intellectual information systems functioning in terms of theoretical computer science.

Abstract: This article describes the method of developing information-reference systems on history of mathematics. The main principles of this method are following. Information is grouped around persons, at that detailed biographical data is classified by chronological view, geographical view, etc. Bibliographical list of person includes either publication by this scientist or publications about this scientist. А connection between scientific activities of researcher with formal description of object domain where this researcher worked is clearly shown. This description includes the information model of the reference book, subsystem's realization features of the information system, and also main types of user information requests which are required for full-featured work with the system.