Topic Maps are candidate tools for SustainableKnowledge
Topic Maps - A Standard For Information Organisationhttp://TopicMaps.Org, have produced a version of the topic map paradigm for use in a web environment which provides an interchange syntax in XML. This XML interchange syntax, known as XTM has since been adopted by ISO and forms part of the ISO 13250 standard in its second edition.
An introduction to TopicMaps can be seen at http://www.ontopia.net/topicmaps/materials/tao.html
"... a topic is an InformationObject? that represents a subject"
It may even represent an object which is not directly available in electronic form for use by the information processor of the computer. A topic "Reifies" its subject, making it available for computer handling.
"There are five things we can add" (to the InformationObject? called a topic):
Topicmaps.Org is an independent consortium of parties interested in developing the applicability of the Topic Maps Paradigm to the World Wide Web, by leveraging the XML family of specifications as required.
This work includes the development of version 1.0 of an XML grammar for interchanging Web-based Topic Maps, called XML Topic Maps (XTM http://www.topicmaps.org/xtm/index.html ) Version 1.0, written by the Topicmaps.Org Authoring Group. All versions of the XTM Specification will be permanently licensed to the public.
Please check the XTM Home Page (http://www.topicmaps.org/xtm/index.html) for links to the specifications, bibliographic and other related information.
Note that we are providing a directory of XTM logos for promotion of XTM. These are available in various formats and sizes. All are Copyright 2000 TopicMaps.Org, All Rights Reserved.
 first fully described in the ISO/IEC 13250:2000 "Topic Maps" standard [ISO13250]