MODS: The Metadata Object Description Schema

Prefatory Commentary from the Editor

Fortunately, the library world is evolving very rapidly. An alphabet soup of initiatives has surfaced in the last few years, many of which may be with us for a long time. These include SPARC, DLF, OAI, W3C, XML, RDF, OWL, DCMI . . . This article is about one of the more recent—MODS, Metadata Object Description Schema, and it may be helpful to provide some background as to why it is important enough to include here. First, for the noncataloging specialist, what is it? In brief, MODS is a drastically simplified set of conventions for cataloging. It may be applied to anything, but many will see it as most useful in the Web environment. A second question: Why is it necessary? I would say primarily because of drawbacks in the Dublin Core.

Rebecca Guenther is one of the designers of MODS. She has spent the greater part of her career at the Library of Congress in standards work, was present at the inception of the Dublin Core, and has been active in its long evolution. Her article, while giving an overview of MODS, also details the reasons why the Dublin Core is inadequate for describing complex digital objects, at least from the library perspective.

There are three major causes that can be adduced for the less than enthusiastic adoption in the library world of the Dublin Core, especially in the arena where it should have been most successful: as a tool for describing Web resources by libraries. First is its incompleteness. After seven years in development, some of its fifteen elements (now sixteen we are told by Ms. Guenther) have yet to receive even cursory qualification or refinement, a precondition for serious use for library applications. The primary miscreants: those elements dealing with the agents responsible for a resource, namely, the Creator, Contributor elements. Along with the Publisher element, also suspect, these have been the object of endless discussions in the Dublin Core community, without issue as nearly as I can make out. They remain as they were initially proposed, naked and unqualified, and as a consequence, inadequate for many uses.

A second indicator of limited success is the absence of a set of accepted (or acceptable) instructions for using the partially completed qualified Dublin Core that has been issued by the Dublin Core Metadata Initiative (DCMI), the title of the organization controlling its evolution. This lack is as lamentable as it is inexplicable. What it causes, among other sad consequences, is the reinvention at every new use, and in every adopting community, of a local set of instructions, a sorry waste of time, as well as a guarantee of inconsistent use in the application. And this for a standard that is notoriously vague and hard to apply.

The third (and primary) indicator of limited success is a result of the first two: its slow adoption, particularly for library applications. Let me state my belief clearly: because the Dublin Core is incomplete and undocumented, it is expensive and difficult to use, and thus fails to provide a convenient, easy to use standard for creating usable resource descriptions for Web objects.

You may very well ask, why should we care? And I would counter: Do libraries have the responsibility for providing access to patrons of knowledge objects on the Web? If your answer is, no, others (specifically, Google) are doing an adequate job, skip this article; indeed, skip 21^st century librarianship. If you answer yes, another question follows: How is this to be done? That is the role the Dublin Core might have played, at least for library practitioners. MODS may offer a better solution. It attempts to provide richer resource descriptions than Dublin Core has been able to do even in its qualified form.

One additional point. MODS is a descriptive metadata format designed to be used with The Metadata Encoding and Transmission Standard, (METS), developed as an initiative of the Digital Library...