Versioning hypermedia

Keeping multiple versions of the same electronic artifact is a necessity in many authoring fields, and a serious advantage in all of them. Hypermedia adds to that the issue of relationship management. This poses a few additio nal problems, especially conceptual ones, but it also provides a reliable a nd safe solution for the well-known problem of the referential integrity of links. The field of hypermedia has dealt with versioning issues for a long time, since Xanadu considered it a fundamental mechanism for its inner wor kings. Newer systems, and an important protocol for the WWW, WebDAV, consti tute modern approaches to the problem.