Languages, Information

specialized artificial languages used in various systems that process information. Information languages should be distinguished from programming and machine languages, which are used for human communication with digital computers, for data description, and for data-processing programs, and from formalized scientific languages designed for symbolic recording of the facts and theories of mathematics, logic, and chemistry. A distinction is also made between an information language for a logical information system (called a logical information language) and an information language for an information retrieval system (an information retrieval language). In principle, however, there is no difference between the two because many information languages can be used in either system. Any information language must ensure unambiguous recording of data and subsequent data recognition with a specified level of thoroughness and accuracy. Logical information languages must also provide formalization of logical deduction.

Information languages have been developed most highly for description of the basic content and primary subject or topic of a text or for an information request to be used in information retrieval (seeINDEXING OF DOCUMENTS). For example, a language for bibliographic description serves as a means to identify texts. It contains bibliographic elements, such as names of authors, titles, scientific institutions, and periodical publications; its chief sphere of application is in alphabetized catalogs, card files, and bibliographic indexes. The language has its own special features in various classification systems (seeLIBRARY-BIBLIOGRAPHICAL CLASSIFI-CATIONS). In descriptor languages (seeDESCRIPTION), the basic content of the text is expressed by a list of words of completely defined semantic content, chosen from a special vocabulary (thesaurus) or from the text itself. Since it serves as a kind of indicator of the coordinates of the text, this kind of indexing is called coordinate indexing.

In semantic codes, the semantic relations between words are expressed not by references in a thesaurus, special tables, or diagrams (as with descriptor languages), but by the actual structures of the words, as in the Perry-Kent semantics code (USA) and the code language of the Institute of Cybernetics of the Academy of Sciences of the Ukrainian SSR. In syntactic languages the semantic relations between words are expressed by the same means as in descriptor languages. Grammatical relations, however, are expressed not by link and role indicators, but rather by an elaborate system of means.