Topic maps provide a standardized way for representing structured information as a set of resources grouped around topics; and as relationships between those topics. The topic map concept is described in detail in the ISO standard ISO/IEC 13250:2000 [ISO13250] , which also specifies a standard interchange syntax based on SGML and HyTime. The XML Topic Maps (XTM) 1.0 specification [XTM] developed by TopicMaps.Org defines an interchange syntax based on XML and XLink. Despite the relatively new status of these standards (the ISO specification was published in January 2000, with the XTM specification being completed in February 2001), commercial and non-commercial implementations of so-called ‘topic map engines’ are already being offered. These ‘engines’ have certain features in common - all provide the means to persistently store data structured as topic maps and to retrieve that data programmatically via an API. Other commercial and non-commercial applications of those engines are also available, including applications to present topic map data in a user-friendly browser-interface and applications to manually or automatically create topic maps from data sources.

This paper does not review the current crop of topic map applications, but instead is intended as a review of real-life applications of the topic map standard to business problems. All of the examples in this paper are extant and are either in production or in trial for production. The goal of this paper is to demonstrate that topic maps can be, and are being, used to effectively solve problems in the business world and to try and reveal some of the reasons for this approach being adopted by the developers of the solutions.