Tendencias de desarrollo de los lenguajes de encabezamientos de materia en las bibliotecas

This paper briefly describes the main development tendencies of the subject heading languages in the context of the international library work. The analyzed tendencies are the convergence of the pre-coordinated and post-coordinated systems, the working out of projects of language compatibility, and the increasing dissemination of the subject heading language of the Library of Congress. The paper also identifies the principles which are set by the International Federation of Library Associations and Institutions and rule the subject heading languages