Terminologies and terminology servers for information environments

Terminologies, or constrained vocabularies, are a potentially rich means of representing the metadata required for applications that have partially structured and incomplete dynamic data to describe, and exploratory and inexact queries to express. Such applications include digital libraries and multimedia repositories and software management; specific application communities include medicine and art. The authors propose that terminologies are ideal for meeting today's information requirements and that a dynamic terminology service is the appropriate architectural approach. They present the requirements of a terminology server, and describe the implementation and practical use of one developed by the authors that uses a description logic, GRAIL, to represent the terms. The terminology server has been extensively used in applications relating to medicine and is being used in the integration of diverse information sources for molecular biology.