Dublin Core is the most common metadata schema for web content.
Named in part for a 1995 metadata conference hosted by the Online Computer Library Center (OCLC) located in Dublin, Ohio, Dublin Core consists of 15 elements that were considered broad and generic enough to describe a wide range of resources.
A name given to the resource, either supplied by the individual assigning metadata or from the object.
Example: "A Pilot's Guide to Aircraft Insurance"
Entity responsible for making the resource.
Example: "Duncan, P. A."
The topic of the resource, typically represented using keywords.
Example: "Colonial medicine"
An account of the resource.
Example: "Illustrated guide to airport markings and lighting signals for airports with low visibility conditions."
An entity responsible for making the resource available.
Example: "The University of Texas Press"
An entity responsible for making contributions to the resource (e.g. editor, transcriber, illustrator).
Example: "Austin Citizen Photograph"
The spatial or temporal topic of the resource.
Example: "Austin, TX"
A point or period of time associated with the resource.
The nature or genre of the resource. For a list of possible types, visit the DCMI Type Vocabulary.
The file format, physical medium, or dimensions of the resource.
Example: " p. : ill. ; 15 cm."
Information about rights held over the resource.
Example: "This electronic resource is made available by the University of Texas Libraries solely for the purposes of research, teaching and private study."
A related resource from which the described resource is derived.
Example: "ZA 3075 Y69 2007"
Language(s) of the resource.
A related resource. For a list of possible relations, visit the Summary Refinement and Scheme Table.
Example: "HasVersion 13th Edition"
A unique reference to the resource.
MARC, an acronym for MAchine-Readable Cataloging, is a widely used standard among libraries. MARC was developed by the Library of Congress in the 1960s to enable computer production of catalog cards.
The MARC record structure contains ten sets of fields, associated with 3-digit numbers called tags. Some fields are further defined by indicators and subfield codes.
|0XX||Control information, numbers, and codes|
Main entries related to personal and corporate names
Example: 100 1# $a Arnosky, Jim.
Titles, edition, imprint information
Example: 245 10 $a Dinosaurs : $b a visual encyclopedia.
Example: 300 ## $a 303 p. : $b col. ill. ; $c 29 cm.
Example: 520 ## $a Presents an illustrated look at dinosaurs.
Subject access entries
Example: 650 #1 $a Dinosaurs.
|7XX||Added entries other than subjects or series|
|8XX||Series added entries and holdings information|
Fields for locally-defined use
Example: 900 ## $a 599.74 ARN
Encoded Archival Description (EAD) was developed in the 1990s by the archival community as a way of presenting finding aids in electronic form. It uses Standard Generalized Markup Language (SGML) and XML as the encoding schemes. Maintained by the Society of American Archivists and the Library of Congress, the latest version is EAD3.
Inside the outermost wrapper element, <ead>, the EAD contains two main sections: <control> and <archdesc>. Each of these sections also include required and optional child elements.
|Encoded Archival Description||Contains all the elements in an EAD document, including Control and Archival Description.|
|Control||Contains elements about the finding aid itself, such as title, author, creation date, language, and description rules used.|
Contains elements describing the content, context, and extent of the archival collection, rather than the finding aid, such as subjects, format, and box and folder inventory.
Metadata Object Description Schema (MODS) is an XML schema with MARC-like semantics. MODS was developed by the Library of Congress out of the need for something easier to learn than MARC and richer than Dublin Core for describing complex digital objects.
MODS is "friendly" because it uses language-based tags rather than the numeric codes (e.g. 250) traditional to MARC. There are 20 top-level MODS elements, many of which contain subelements for granular desription.
MODS Top-Level Elements
|Title Information||Contains all subelements related to title information.|
|Name||Contains all subelements related to information about the name of a person, organization, or event (conference, meeting, etc.) associated in some way with the resource.|
|Type of Resource||Information about the original item that specifies the characteristics and general type of content of the resource, as chosen from a defined list of terms.|
|Genre||A term that give more specificity for the form, style, or content of an object than the broad terms used in Type of Resource.|
|Origin Info||Contains subelements related to place of origin or publication, publisher/originator, and dates associated with the resource.|
|Language||Contains a subelement to record the language in which the language of the content of a resource is expressed.|
|Physical Description||Contains all subelements relating to physical attributes of the resource.|
|Abstract||A succinct summary of the content of the resource.|
|Table of Contents||A description of the contents of a resource.|
|Target Audience||A description of the intellectual level of the audience for which the resource is intended.|
|Note||General textual information relating to a resource, that is not encoded in other more specific elements.|
|Subject||Contains subelements relating to the primary topic(s) on which a work is focused.|
|Classification||Indication of the subject via a formal system of coding and organizing resources (e.g. call number).|
|Related Item||Contains subelements with information that identifies other resources related to the one being described.|
|Identifier||A unique standard number or code that distinctively identifies a resource.|
|Location||Contains subelements that identify the institution or repository holding the resource, or the electronic location in the form of a URL when available.|
|Access Condition||Information about restrictions imposed on access to a resource.|
|Part||Contains subelements to designate physical parts of a resource in detail.|
|Extension||Provides additional information not covered by MODS (when local elements or elements from other standard schemas are needed).|
|Record Info||Contains subelements relating to information necessary to managing metadata.|
METS stands for Metadata Encoding and Transmission Standard. Developed by the Library of Congress, it facilitates the encoding of metadata for materials within digital libraries.
The METS document structure consists of seven possible sections which may contain a variety of subelements and attributes, and relies on externally defined schemas for descriptive and administrative metadata.
|METS Header||Contains metadata describing the METS document itself, including information such as creator, date of creation, and editor.|
|Descriptive Metadata||Internally or externally points to extension descriptive metadata schemas, such as PREMIS, MODS, or Dublin Core. For a list of approved "best practice" metadata schemas, visit External Schemas for Use with METS.|
|Administrative Metadata||Internally or externally points to extension administrative or technical metadata schemas, such as the Library of Congress schemas for A/V technical metadata.|
|File Inventory||Lists all files containing content which comprise the electronic versions of the digital object, such as thumbnails, master archival images, or PDF versions.|
|Structural Map||Defines a hierarchical structure which allows users to navigate through the digital object.|
|Structural Links||Records the existence of hyperlinks between items within the structural map.|
|Behavior||Associates executable code with content in the METS object, such as a page-turning program.|
VRA Core is a standard commonly employed by cultural heritage organizations to describe images and works of art. VRA Core is hosted by the Visual Resources Association (VRA) and the Library of Congress.
VRA Core contains 19 elements. There are three primary entities: Work (a built or created object), Collection (an aggregate of such objects), and Image (a visual surrogate of such objects).
|Work, Collection, or Image||A record is described as a Work, a Collection, or an Image.|
|Agent||Individual, group, or corporate body that has contributed to the design, creation, production, etc. of the work.|
|Cultural Context||Name of the culture, people, or country with which the work has been associated.|
|Date||Date associated with the work.|
|Description||Free-text note about the work that gives additional information not in other categories.|
|Inscription||All marks added to the work at the time of production (e.g. signatures or stamps).|
|Location||Geographic location or repository whose boundaries include the work.|
|Material||Substance which the work is composed of (e.g oil paint, bronze, or graphite).|
|Measurements||Dimensions of the work.|
|Relation||Terms describing the relationship between the work and a related work.|
|Rights||Information about the copyright status for the work.|
|Source||Reference to the source of information recorded about the work.|
|State Edition||Identifying number or name assigned to the edition of a work that exists in more than one form.|
|Style Period||Defined style, historical period, school, or movement whose characteristics are represented in the work.|
|Subject||Terms that describe the work.|
|Technique||Production processes, techniques, and methods incorporated in the fabrication of the work.|
|Textref||Unique identifier assigned to the work.|
|Title||Title given to the work.|
|Work Type||Identifies the specific type of Work, Collection, or Image being described in the record.|
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