Title:               DCMI Metadata Terms - an Overview
Maintainer:          Thomas Baker, Usage Board Chair
Identifier:          http://dublincore.org/usage/terms/
Latest version:      http://dublincore.org/usage/terms/
Installed as:        http://dublincore.org/usage/terms/index.shtml
Date Last Modified:  2002-04-27


The DCMI Usage Board currently maintains two sets of metadata
terms:

-- DCMI Elements and Qualifiers
   http://dublincore.org/usage/terms/elements-qualifiers/

-- DCMI Type Vocabulary
   http://dublincore.org/documents/dcmi-type-vocabulary/

The Usage Board is responsible for maintaining these term sets
from a "semantic" point of view.  The policies and processes
governing such maintenance are described in a Namespace Policy
[NAMESPACE], the Usage Board's Mission and Principles
[PRINCIPLES], Usage Board Administrative Processes [PROCESS].

DCMI -- the words we use

These foundation documents cited above use a particular jargon:
"DCMI terms" are elements, qualifiers, or terms in controlled
vocabularies maintained by DCMI. Each DCMI term is defined in a
DCMI recommendation and is uniquely identified by a Uniform
Resource Identifier (URI) within a DCMI namespace.  A "DCMI
recommendation" is a human-readable document that may define one
or more DCMI terms.  A "DCMI namespace" is a collection of DCMI
terms, where each namespace is identified by a URI and each term
is identified by a URI formed from the "name" of a term (e.g.,
title) prefixed by the URI of a DCMI namespace, as in
http://purl.org/dc/elements/1.1/title and
http://purl.org/dc/terms/audience.

A "DCMI term declaration" is the machine-processable
representation of one or more DCMI terms, expressed in a schema
language.  The technical specifications of such representations
are within the scope of Usage Board control only to the extent
that alternative machine-processable encodings may have
different semantic implications.  As of April 2002, the goal of
DCMI is to make its metadata semantics available for machine
processing in a wide range of XML and Semantic Web applications.

Dublin Core has Elements and Qualifiers.  A Dublin Core
"Element" is a property of a resource.  A "Qualifier" can be
either an Element Refinement or an Encoding Scheme.  An "Element
Refinement" is a term with a narrower meaning with respect to a
particular Element.  An "Encoding Scheme" is a pointer to
contextual information that aids in the interpretation of an
element value.  A value expressed using an encoding scheme is
usually a term selected from a controlled vocabulary (e.g., a
classification system or set of subject headings) or a string
formatted in accordance with a formal notation (e.g.,
"2000-01-01" as a template for dates).

The DCMI Type Vocabulary provides a general, cross-domain list
of approved terms that may be used as values for the Resource
Type element to identify the genre of a resource.  It is
currently the only controlled vocabulary of values maintained by
DCMI.

References

[NAMESPACE] http://dublincore.org/documents/dcmi-namespace/
[PRINCIPLES] http://dublincore.org/usage/documents/mission/
[PROCESS] http://dublincore.org/usage/documents/process/