Final Draft

The Dublin Core Metadata Glossary is a collaborative effort of the User Guide Committee with special thanks to Gail Clement & Pete Winn, whose original glossary was a basis for this version. Terms included in this glossary are based on Dublin Core documents, presentations at DC conferences, and discussions on the DC General listserv. We welcome comments and feedback regarding additions, deletions or changes to the terms and/or definitions found below.

For related links, including the guide itself, see this site's home page.

A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z

 

1:1 principle

The principle whereby related but conceptually different entities, for example a painting and a digital image of the painting, are described by separate metadata records.

A

 

AACR2

See Anglo-American Cataloguing Rules

administrative metadata

Metadata used in managing and administering information resources, e.g., location or donor information. Includes rights and access information, data on the creation and preservation of the digital object.

Anglo-American Cataloguing Rules (AACR2)

The dominant bibliographic standard regulating cataloging in the English-speaking world.  AACR2 represents a set of rules for the standard description of and access to all materials which a library holds or to which it has access.

American Standard Code for Information Interchange (ASCII)

A scheme that provides standard numeric values to represent letters, numbers, punctuation marks and other characters.  The use of standard values allows computers and computer programs to exchange data.

application profile

A set of metadata elements, policies, and guidelines defined for a particular application. The elements may be from one or more element sets, thus allowing a given application to meet its functional requirements by using metadata from several element sets including locally defined sets. For example, a given application might choose a subset of the Dublin Core that meets its needs, or may include elements from the Dublin Core, another element set, and several locally defined elements, all combined in a single schema. An Application profile is not complete without documentation that defines the policies and best practices appropriate to the application.

ASCII

See American Standard Code for Information Interchange

Author

See Creator

authority control

A set of rules or procedures that maintain consistency for accessing names or terms within a database. Means of establishing a consistent form of the name or concept through authority records.

authority file

A collection of authority records.

authority record

A record that shows the preferred form of a personal or corporate name, geographic region or subjects. It indicates variant forms of the established heading.

B

 

Basic Semantics Register

An ISO Standard ISO/TS 16668:2000 which identifies and defines semantic components for use in data exchange.

best practice

Guide and documentation to describe and standardize the use of metadata elements that best support a community's needs.

BSR

See Basic Semantics Register

C

 

case-sensitive

Lower and upper case letters are not treated as being the same; e.g. 'a' is not the same as 'A'.

classification

A logical scheme for arrangement of knowledge, usually by subject. Classification schema are alpha and/or numeric; for example, Library of Congress Classification, Dewey Classification, Universal Decimal Classification.

controlled vocabulary

A prescribed set of consistently used and carefully defined terms.

Contributor

The Dublin Core element used to designate the entity responsible for making contributions to the content of the resource. Examples of a Contributor include a person, an organization or a service. Typically, the name of a Contributor should be used to indicate the entity. See also section 4 of the Dublin Core Users Guide.

Coverage

The Dublin Core element used to designate the extent or scope of the content of the resource. Coverage will typically include spatial location (a place name or geographic co-ordinates), temporal period (a period label, date, or date range) or jurisdiction (such as a named administrative entity). Recommended best practice is to select a value from a controlled vocabulary, and that, where appropriate, named places or time periods be used in preference to numeric identifiers such as sets of co-ordinates or date ranges. See also section 4 of the Dublin Core Users Guide.

Creator

The Dublin Core element used to designate the entity primarily responsible for making the content of the resource. Examples of a Creator include a person, an organization, or a service. See also section 4 of the Dublin Core Users Guide.

Crosswalk

A table that maps the relationships and equivalencies between two or more metadata formats. Crosswalks or metadata mapping support the ability of search engines to search effectively across heterogeneous databases, i.e. crosswalks help promote interoperability.

D

 

Date

The Dublin Core element used to designate the date associated with an event in the life cycle of the resource. Typically, Date will be associated with the creation or availability of the resource. See also section 4 of the Dublin Core Users Guide.

DCMES

Dublin Core Metadata Element Set. See Dublin Core.

DCMI

See Dublin Core Metadata Initiative

Description

The Dublin Core element used to designate a textual description of the content of the resource. See also section 4 of the Dublin Core Users Guide.

DCSV

See Dublin Core Structured Value

descriptive metadata

Metadata that supports the discovery of a digital object.

digital tourist

An inexperienced searcher in the digital environment who does not possess knowledge of community- specific vocabularies. The Dublin Core provides a rudimentary vocabulary, or "pidgin language" for information discovery when exploring new digital territories. Coined by Ricky Erway at the Metadata Workshop on Metadata for Networked Images, September 24-25, 1996.

discovery software

A computer application designed to simplify, assist and expedite the process of finding information resources.

Document Object Identifier

DOI was developed by the International DOI Foundation as a system for identifying and exchanging intellectual property in the digital environment.

Document Type Definition (DTD)

In SGML or XML, a formal description of the components of a specific document or class of documents. DTDs provide a formal grammar used for machine processing (parsing) of documents expressed in SGML or XML. A DTD description includes:

• The containers or elements that make up the document; e.g., paragraphs, headings, list items, figures, tables, etc.
• The logical structure of the document; e.g., chapters containing sections, etc.
• Additional information associated with elements (known as attributes); e.g., identifiers, date stamps, etc.

document-like object (DLO)

Originally defined as an entity that resembles a document from the standpoint that it is substantially text-based and shares other properties of a document; e.g., electronic mail messages or spreadsheets. The definition was expanded at the 3rd DC workshop to refer to any discrete information resource that are characterized by being fixed (i.e., having identical content for each user). Examples include text, images, movies, and performances.

DOI

see Document Object Identifier

dot.syntax

A mechanism for refining the meaning of the element in HTML; for example, <META NAME="DC.Title.Alternative" CONTENT="Title">

DTD

See Document Type Definition

Dublin Core

The Dublin Core is a 15-element metadata element set intended to facilitate discovery of electronic resources. The Dublin Core has been in development since 1995 through a series of focused invitational workshops that gather experts from the library world, the networking and digital library research communities, and a variety of content specialties. See Section 1 of this guide or the Dublin Core Web Site.

Dublin Core Metadata Initiative

Dublin Core Metadata Initiative, the body responsible for the ongoing maintenance of Dublin Core. DCMI is currently hosted by the OCLC Online Computer Library Center, Inc., a not-for-profit international library consortium. The work of DCMI is done by contributors from many institutions in many countries. DCMI is a consensus-driven organization organized into working groups to address particular problems and tasks. DCMI working groups are open to all interested parties. Instructions for joining can be found at the DCMI web site under Working Groups (http://dublincore.org)

Dublin Core Structured Values

DCSV recognizes two types of substrings: labels and values. A label is the name of the type of a value, and a value is the data itself. A value that is comprised of components, i.e. a value which has its own label and value, is called a structured value. Punctuation supports the parsing of the DCSV.

Dumb-down Principle

A rule for the application of Interoperability Qualifiers, which stipulates that qualifiers can refine but not extend the meaning of the element to which they are applied. Thus, ignoring a qualifier ("dumbing down" the qualifier) may cause a loss of precision, but the resulting value should still be of some use to an application or user.

E

 

EAD

see Encoded Archival Description

electronic information resource

An information resource that is maintained in electronic, or computerized format, and may be accessed, searched and retrieved via electronic networks or other electronic data processing technologies (e.g., CD-ROM)

element

A discrete unit of data or metadata. An element may contain subelements that are called qualifiers in Dublin Core.

element refinement (qualifier)

Qualifiers make the meaning of an element narrower or more specific.

embedded metadata

Metadata that is maintained and stored within the object it describes; the opposite of stand-alone metadata.

Encoded Archival Description

An SGML DTD that represents a highly structured way to create digital finding aids for a grouping of archival or manuscript materials.

encoding scheme

A scheme that aids in the interpretation of an element value. These schemes include controlled vocabularies and formal notations or parsing rules. A value expressed using an encoding scheme will thus be a token selected from a controlled vocabulary (e.g., a term from a classification system or set of subject headings) or a string formatted in accordance with a formal notation.

extensible

Having the potential to be expanded in scope, area or size. In the case of Dublin Core, the ability to extend a core set of metadata with additional elements.

Extensible Markup Language (XML)

A subset of Standard Generalized Markup Language (SGML), a widely used international text processing standard. XML is being designed to bring the power and flexibility of generic SGML to the Web, while maintaining interoperability with full SGML and HTML. For more information, see http://www.w3.org/XML/

F

 

Format

The Dublin Core element used to designate the physical or digital manifestation of the resource. See also section 4 of the Dublin Core Users Guide.

G

 

GIF

See Graphics Interchange Format

GILS

See Global Information Locator Service

glossary

An alphabetized list of terms with definitions often created by an organization to reflect its needs. Normally lacks hierarchical arrangement or cross references. Also known as a term list.

Global Information Locator Service (GILS)

GILS embraces open standards to implement interoperable searching across diverse, decentralized information 'locators' to return references to all kinds of electronic and non-electronic information resources. Locators are implemented as common semantics for characterizing information resources, i.e. common metadata semantics. Formally known as Government Information Locator Service.

Graphics Interchange Format (GIF)

The dominant graphics format on the Web, limited to 256 colors. GIFs provide sharper black & white images than JPEGs.

granularity

The level of detail at which an information object or resource is viewed or described.

H

 

HTML

See Hypertext Markup Language

Hypertext Markup Language (HTML)

The standard text-formatting language for documents on the World Wide Web. HTML text files contain content that is rendered on a computer screen and markup, or tags, that can be used to tell the computer how to format that content. HTML tags can also be used to encode metadata and to tell the computer how to respond to certain user actions, such as a mouse click. For more information, see http://www.w3.org/MarkUp/.

I

 

Identifier

The Dublin Core element that is an unambiguous reference to the resource within a given context. Recommended best practice is to identify the resource by means of a string or number conforming to a formal identification system. See also section 4 of the Dublin Core Users Guide.

IETF

See Internet Engineering Task Force

indexing

The process of evaluating information entities and creating indexing terms, normally subject or topical terms, that aid in finding and accessing the entity. Index terms may be in natural language or controlled vocabulary or a classification notation.

IMT

See Internet Media Type

indexing program

Computer software used to order things; frequently used to refer to software that alphabetizes some or all of the terms in one or more electronic documents.

information resource

Any entity, electronic or otherwise, capable of conveying or supporting intelligence or knowledge; e.g. a book, a letter, a picture, a sculpture, a database, a person. See also DLO

instantiation

An identifiable occurrence or occasion of something; in the case of Dublin Core, a specific occurrence of an information resource.

International Organization for Standardization

ISO was established in 1947 as a worldwide federation of national standards bodies from some 130 countries.

Internet Commons

The global Internet environment, collection of information-bearing repositories whose data can be accessed through the Internet.

Internet Engineering Task Force (IETF)

The IETF is responsible for solving short-term engineering needs of the Internet. It has over 40 Working Groups.

Internet Media Type (IMT)

A set of terms that describe types of resources on the Internet. Used as an encoding scheme for the Format element in Dublin Core. http://isi.edu/in-notes/iana/assignments/media-types/media-types

interoperability

The ability of different types of computers, networks, operating systems, and applications to work together effectively, without prior communication, in order to exchange information in a useful and meaningful manner. There are three aspects of interoperability: semantic, structural and syntactical.

Interoperability Qualifiers

Additional metadata used either to refine the semantics of a Dublin Core metadata element's value, or to provide more information about the encoding scheme used for the value.

ISO

See International Organization for Standardization

J

 

Joint Photographic Experts Group (JPEG)

A standard for compressing digital images. The advantage of JPEG is that it uses compression to make graphics files smaller, making them faster to transfer and view over the World Wide Web. More than 16 million color hues are available. Better than GIF for color photographs. The disadvantage is some loss of image quality due to data loss during compression.

JPEGs

See Joint Photographic Experts Group

K

 

Keywords

See Subject

L

 

Language

The Dublin Core element used to designate the language of the intellectual content of the resource. Recommended best practice for the values of the Language element is defined by RFC 3066 See also section 4 of the Dublin Core Users Guide.

literal

A literal or "appropriate literal" is the value of any given metadata entity that can be either a hyperlink or a string value (literal). A literal affords a great deal of flexibility and power, but increases complexity. Metadata should as well include an appropriate literal that reflects the base value of the metadata entity. For example, in these fragments: creator = "Public, John Q." creator = " http://authority.org/public-john-q-1234" the first has a value expressed as an appropriate literal whereas the second has a (hypothetical) link to an authority structure. It is not entirely clear what a person or application will find at the end of the link, so the metadata should contain an appropriate literal for simple discovery purposes.

M

 

mapping metadata

See crosswalk

MARC

Machine-Readable Cataloging Record. The MARC formats are standards for the representation and communication of bibliographic and related information (authority, holdings, classification, community information) in machine-readable form. MARC 21 grew out of the harmonization of USMARC and CAN/MARC, formerally national standards, and has emerged as an international standard. MARC21 is an implementation of the American National Standard, Information Interchange Format (ANSI Z39.2) and its international counterpart, Format for Information Exchange (ISO 2709). UniMARC was originally designed for conversion between national formats but now has been adopted by some countries as their national standard.

META tag

The HTML element used to demarcate metadata on a Web page. <META> </META>.

metadata

In general, "data about data;" functionally, "structured data about data." Information about an information resource. In the case of Dublin Core, information that expresses the intellectual content, intellectual property and/or instantiation characteristics of an information resource. See Section 1.1 of this guide.

metadata record

A syntactically correct representation of the descriptive information (metadata) for an information resource. In the case of Dublin Core, a representation of the Dublin Core elements that has been defined for the resource. The majority of metadata records and record fragments in this document are presented in HTML syntax.

Metadata registry

A publicly accessible system that records the semantics, structure and interchange formats of any type of metadata. A formal authority, or agency, maintains and manages the development and evolution of a metadata registry. The authority is responsible for policies pertaining to registry contents and operation.

MIME

See Multipurpose Internet Mail Extensions

Multipurpose Internet Mail Extensions

The standard for attaching files to Internet e-mail messages. Attached files may be text, graphics, spreadsheets, documents, sound files, etc.

N

 

National Information Standards Organization

NISO, accredited by ANSI, develops and promotes technical standards used in a wide variety of information services.

namespace

A unique name that identifies an organization that has developed an XML schema. A namespace is identified via a Uniform Resource Identifier (a URL or URN). For example, the namespace for Dublin Core elements and qualifiers would be expressed respectively in XML as:

xmlns:dc = "http://dublincore.org/elements/1.0/"

xmlns:dcq = "http://dublincore.org/qualifiers/1.0/" >

The use of namespaces allows the definition of an element to be unambiguously identified with a URI, even though the label "title" alone might occur in many metadata sets. In more general terms, one can think of any closed set of names as a namespace. Thus, a controlled vocabulary such as the Library of Congress Subject Headings, a set of metadata elements such as DC, or the set of all URLs in a given domain can be thought of as a namespace that is managed by the authority that is in charge of that particular set of terms.

networked resource

An object that is available electronically via a network.

NISO

See National Information Standards Organization

O

 

OCLC

See Online Computer Library Center

Online Computer Library Center (OCLC)

The major source of cataloging data for libraries around the world; located in Dublin, Ohio, US.

P

 

parsing

Parsing may be divided into parts: lexical analysis and semantic parsing. Lexical analysis divides strings into components based on punctuation or tagging. Semantic parsing then attempts to determine the meaning of the string.

Persistent Uniform Resource Locator

An approach to the URL permanence problem proposed by OCLC. A PURL is a public alias for a document. A PURL remains stable, while the document's background URL will change as it is managed (e.g. moved) over time. A PURL is created by a Web administrator who is registered as a PURL "owner" and who maintains a mapping of the PURL to a current and functioning URL. A PURL is a form of URN.

Publisher

The Dublin Core element used to designate the entity responsible for making the resource available. Examples of a Publisher include a person, an organization, or a service. Typically, the name of a Publisher should be used to indicate the entity. See section 4 of the Dublin Core Users Guide.

PURL

See Persistent Uniform Resource Locator

Q

 

qualifier

Something that describes or characterizes an object. In the case of Dublin Core, a qualifier refines an element's meaning. A qualifier must follow the Dumb-Down Principle. There are two broad categories of qualifiers: Encoding schema and Element refinement.

R

 

RDF

See Resource Description Framework.

RDF Site Summary

RSS was created and popularized by Netscape for their personalized portal site. Rich Site Summary (RSS) is a lightweight XML application designed to exchange headline metadata between news content providers and portals.

registry

A system to provide management of metadata elements. Metadata registries are formal systems that provide authoritative information about the semantics and structure of data elements. Each element will include the definition of the element, the qualifiers associated with it, mappings to multilingual versions and elements in other schema.

Relation

The Dublin Core element used to designate A reference to a related resource. Recommended best practice is to reference the resource by means of a string or number conforming to a formal identification system. See section 4 of the Dublin Core Users Guide.

Request for Comment (RFC)

A Request for Comment (RFC) is the process of establishing a standard on the Internet. Discussion of the proposed standard on the Internet is facilitated by the Internet Engineering Task Force (IETF). Once approved, the standard receives a unique number which identifies it; e.g., RFC See http://www.isi.edu/rfc-editor/. and http://www.ietf.org/rfc.html

Resource Description Framework (RDF)

The basic language for writing metadata; a foundation which provides a robust flexible architecture for processing metadata on the Internet. RDF will retain the capability to exchange metadata between application communities, while allowing each community to define and use the metadata that best serves their needs. For more information see http://www.w3.org/RDF/

resource discovery

The process through which one searches and retrieves an information resource.

Resource Type

See Type.

Resource Description

See Description.

Resource Identifier

See Identifier

RFC

See Request for Comment

Rights

The Dublin Core element used to provide a link to information about rights held in and over the resource. Typically a Rights element will contain a rights management statement for the resource, or reference a service providing such information. Rights information often encompasses Intellectual Property Rights (IPR), Copyright, and various Property Rights. If the rights element is absent, no assumptions can be made about the status of these and other rights with respect to the resource. See section 4 of the Dublin Core Users Guide.

Rights Management

See Rights

ROADS

Resource Organisation And Discovery in Subject based services. A UK funded project whose aim is to develop discovery software for Internet resources.

RSS

See RDF Site Summary .

S

 

scheme

A scheme, or schema, is a systematic, orderly combination of elements. A set of rules for encoding information that supports a specific community of users.

search engine

A utility capable of returning references to relevant information resources in response to a query.

semantic interoperability

Is achieved through agreements about content description standards; for example, Dublin Core, Anglo-American Cataloging Rules.

Semantic Web

A term coined by Tim Berners-Lee which views the future Web as a web of data, like a global database. The infrastructure of the Semantic Web would allow machines as well as humans to make deductions and organize information. The architectural components include semantics (meaning of the elements), structure (organization of the elements), and syntax (communication). http://www.w3.org/DesignIssues/Semantic.html

semantics

Significance or meaning. In the case of Dublin Core, the significance or intended meaning of individual metadata elements and their components.

SGML

See Standard Generalized Markup Language

SICI

Serial Item and Contribution Identifier (ANSI/NISO Z39.56-1996 Vers. 2) A numeric notation to identify serial issues and articles uniquely regardless of their distribution medium (paper, electronic, microform).

software agent

A computer program that carries out tasks on behalf of another entity. Frequently used to reference a program that searches the Internet for information meeting the specified requirements of an individual user.

Source

The Dublin Core element used to designate a reference to a resource from which the present resource is derived. The present resource may be derived from the Source resource in whole or part. Recommended best practice is to reference the resource by means of a string or number conforming to a formal identification system.See also section 4 of the Dublin Core Users Guide.

Standard Generalized Markup Language (SGML)

A non-proprietary language/enabling technology for describing information. Information in SGML is structured like a database, supporting rendering in and conversion between different formats. Both XML and later versions of HTML are instances of SGML. For more information see http://www.w3.org/SGML/.

stand-alone metadata

Metadata that is created, maintained and stored independently of the object it describes. The opposite of embedded metadata.

structured value

See Dublin Core Structured Value

structural interoperability

Is achieved through data models for specifying semantic schemas in a way that they can be shared; for example, RDF.

structural metadata

Structural metadata defines the digital object’s internal organization and is needed for display and navigation of that object.

Sub-element

See element refinement

Subject

The Dublin Core element used to designate the topic of the resource. The element may use controlled vocabularies or keywords or phrases that describe the subject or content of the resource. See also section 4 of the Dublin Core Users Guide.

Subject Headings

An alphabetical list of words or phrases that represent a concept that is under authority control, e.g., the Library of Congress Subject Headings.

surrogate content

Metadata as a substitute for an actual resource.

switching language

A mediating language used to establish equivalencies among various indexing languages. Dublin Core has been viewed as a switching "language" between various metadata schemas.

syntactic interoperability

Achieved by marking up our data in a similar fashion so we can share the data and so that our machines can understand and take the data apart in sensible ways; for example, XML, EAD and MARC.

syntax

The form and structure with which metadata elements are combined. In the case of Dublin Core, the form and structure of how metadata elements and their components are combined to form a metadata record.

T

 

TEI

See Text Encoding Initiative

temporal

Limited by or in regard to time.

Text Encoding Initiative (TEI)

An international project to develop guidelines for the preparation and interchange of electronic texts for scholarly research as well as a broad range of other language industry uses. The TEI DTD is an SGML Document Type Definition for encoding literary works. For more information, see http://www-tei.uic.edu/orgs/tei/info/teij16.html

thesaurus

A controlled vocabulary of terms or concepts that are structured hierarchically (parent/child relationships) or as equivalences (synonyms), and related terms (associative). See also Subject headings and glossary.

Thesaurus of Geographic Names

The TGN is a controlled vocabulary containing around 1,000,000 names and other information about places. It includes physical features and administrative entities, such as cities and nations. The emphasis in TGN is on places important for art and architecture.

Title

The Dublin Core element used to designate the name given to the resource. Typically, a Title will be a name by which the resource is formally known. See also section 4 of the Dublin Core Users Guide.

tokens

The means to denote the status of an element or qualifier within a registry; e.g., proposed, recommended, conforming (to the namespace), obsolete, or local.

Type

The Dublin Core element used to designate the nature or genre of the content of the resource. Type includes terms describing general categories, functions, genres, or aggregation levels for content. Recommended best practice is to select a value from a controlled vocabulary See also section 4 of the Dublin Core Users Guide

U

 

ULAN

See Union List of Artist Names

Unicode

A universal encoding scheme designed to allow interchange, processing and display of the world's principal languages, as well as many historic and archaic scripts. Unicode supports and fosters a multilingual computing world community by allowing computers using one language to "talk" to computers using a different language. A registered trademark of Unicode, Inc.

Unicode Transformation Format, 8-bit (UTF-8)

A temporary form of Unicode that is well suited for routing data through systems that are not designed for Unicode, such as some email servers and Web clients. UTF-8 is an attractive way of storing multilingual data on the Internet, without requiring full Unicode compliance.

Uniform Resource Identifier (URI)

The syntax for all names/addresses that refer to resources on the World Wide Web. For information about Internet addressing, see http://www.w3.org/Addressing/Addressing.html.

Uniform Resource Locator (URL)

A technique for indicating the name and location of Internet resources. The URL specifies the name and type of the resource, as well as the computer, device and directory where the resource may be found. The URL for Dublin Core Metatdata Initiative http://dublincore.org/. For information about Internet addressing, see http://www.w3.org/Addressing/Addressing.html.

Uniform Resource Name (URN)

A URI (name and address of an object on the Internet) that has some assurance of persistence beyond that normally associated with an Internet domain or host name. For information about Internet addressing, see http://www.w3.org/Addressing/Addressing.html.

Union Lists of Artists' Names (ULAN)

Union List of Artist Names. A controlled vocabulary of artists' names and biographical and bibliographic information produced by the Getty Vocabulary Program.

URI

See Uniform Resource Identifier

URL

See Uniform Resource Locator

URN

See Uniform Resource Name

USMARC

See MARC

UTF-8

See Unicode Transformation Format, 8-bit.

V

 

value qualifier

Value qualifier refers to either an encoding rule or controlled vocabulary that aids in the interpretation of the value within the metatag. See encoding scheme.

vcard

A standard for storing information about individuals or corporations; an electronic business card.

For more information, check the Internet Mail Consortium page on personal data exchange.

W

 

Warwick Framework

An architecture for the interchange of metadata packages, or "containers"; designed to satisfy the need for competing, overlapping, and complementary metadata models. For more information, see http://www.dlib.org/dlib/july96/07weibel.html.

World Wide Web (WWW)

The panoply of Internet resources (text, graphics, audio, video, etc.) that are accessible via a Web browser.

World Wide Web Consortium (W3C)

An international industry consortium founded in October 1994 to lead the World Wide Web to its full potential by developing common protocols that promote its evolution and ensure its interoperability. For additional information see http://www.w3.org/Consortium/.

WWW

See World Wide Web

W3C

See World Wide Web Consortium

X

 

XML

See Extensible Markup Language

Y

Z

 

Z39.50

A NISO standard for an application layer protocol for information retrieval which is specifically designed to aid retrieval from distributed servers. http://lcweb.loc.gov/z3950/agency