ASC Central Salesian Archive

Metadata

The Central Salesian Archive is progressively adapting the database that holds the records of the archival units to the international metadata standard known as Dublin Core. Associating the individual fields of each catalogue record with the metadata system improves the retrieval of information through general-purpose search engines. Dublin Core is made up of a core set of elements essential for describing any digital material (e.g. documents, video, images, physical resources, books, CDs, and objects such as works of art, etc.) over the network.

The Dublin Core set: use and applicability

The Dublin Core metadata community arose in Ohio (USA) within the framework of the Online Computer Library Center (OCLC), bringing together producers, authors and rights holders of networked documentation in order to provide tools for access to digital resources. The minimum set proposed in December 1996 consists of 15 basic elements and has also been extended to sub-elements or qualifiers: the standard is under development, but the so-called “core of 15 description elements” has remained stable. Each element is defined using a set of 10 attributes derived from the ISO 11179 standard.

The updated version of the DC format is characterised by: simplicity of use (addressed to both non-cataloguers and specialists); semantic interoperability (establishing a common network of data agreed in meaning and value); the promotion of a useful tool for an international-level infrastructure; and flexibility (allowing the data structure to be integrated and developed with different semantic meanings appropriate to the application context). It also aims to offer an alternative, for digital material, to the more elaborate cataloguing formats of the library world (e.g. the MARC record formats). For this reason the ICCU produced the Italian translation of the latest version of the DC.

Description of the elements

Each Dublin Core element is defined using the ten attributes of the ISO/IEC 11179 standard for data description.

ISO/IEC 11179 attributes

AttributeDescription
NameThe label assigned to the data element
IdentifierThe unique identifier assigned to the data element
VersionThe version of the data element
Registration AuthorityThe entity authorised to register the data element
LanguageThe language in which the data element is specified
DefinitionA statement clearly representing the concept and essential nature of the data element
ObligationWhether the element is always or only sometimes required (contains a value)
DatatypeThe type of data that can be represented in the value of the data element
Maximum OccurrenceA limit to the repeatability of the data element
CommentA remark concerning the application of the data element

Six of these ten attributes are common to all DC elements and are not repeated in the definitions below, as they are part of them:

AttributeValue
Version1.1
Registration AuthorityDublin Core Metadata Initiative
Languageen
Obligationoptional
Datatypecharacter string
Maximum Occurrenceunlimited

The 15 Dublin Core elements

#ElementIdentifierDefinitionComment
1TitleTitleA name given to the resource.Typically, the name by which the resource is formally known.
2CreatorCreatorAn entity primarily responsible for making the content of the resource.E.g. a person, an organisation or a service; the entity’s name is used.
3SubjectSubjectThe topic of the content of the resource.Keywords, key phrases or classification codes; a controlled vocabulary or formal scheme is recommended.
4DescriptionDescriptionAn account of the content of the resource.E.g. an abstract, a table of contents, a reference to a graphic representation or free text.
5PublisherPublisherAn entity responsible for making the resource available in its present form.E.g. a person, an organisation or a service; the entity’s name is used.
6ContributorContributorAn entity responsible for making contributions to the content of the resource.E.g. a person, an organisation or a service; the entity’s name is used.
7DateDateA date associated with an event in the life cycle of the resource.Usually creation or availability; recommended format YYYY-MM-DD (ISO 8601).
8TypeTypeThe nature or genre of the content of the resource.Categories, functions, genres or aggregation levels; a controlled vocabulary is recommended (DCMI Type). For the physical/digital manifestation use Format.
9FormatFormatThe physical or digital manifestation of the resource.Media type or dimensions; useful to determine required software/hardware. A controlled vocabulary is recommended (MIME).
10IdentifierIdentifierAn unambiguous reference to the resource within a given context.A formal identification system: URI (incl. URL/URN), DOI, ISBN.
11SourceSourceA reference to a resource from which the present resource is derived.Full or partial derivation; identify by a formal system.
12LanguageLanguageThe language of the intellectual content of the resource.RFC 1766: ISO 639 code (2 letters) + optional ISO 3166 country code. E.g. it, en, en-uk.
13RelationRelationA reference to a related resource.Identify by a formal identification system.
14CoverageCoverageThe extent or scope of the content of the resource.Spatial location, temporal period or jurisdiction; a controlled vocabulary is recommended (TGN), using names/periods rather than coordinates.
15RightsRightsInformation about rights held in and over the resource.Typically IPR, copyright and property rights, or a link to a service providing such information. If absent, no assumptions may be made about rights.

Sources and references