Metadata

Draft

Definition

From the Wikipedia:Metadata: Metadata (Greek: meta- + Latin: data "information"), literally "data about data", are information about another set of data.

Standards of interest to education

Languages to create taxonomies for objects like web pages or learning objects

• Dublin Core
• Learning Object Metadata Standard

Bibliographic

• Library standards such as MARC
• Bibliographic Citation standards like APA (see also reference managers)

Organizing, describing information

• Information Space standards such as Topic maps or more sophisticated RDF/OWL based semantic networks
• RSS

Folksomic (natural) tagging

• See tagging and tag cloud

Technical representation formats

XML

• Most standards are today published as XML and most of these are built on top of RDF. But there can be multiple representation formats for a given standard. E.g. for Dublin core, one could use XHTML Meta tags or an XML file or fill in a form that then goes to a database.

XHTML Meta Data Profiles

XMDP is a simple XHTML-based format for defining HTML meta data profiles easy to read and write by both humans and machine. An example would be XFN (XHTML Friends Network, a simple way to represent human relationships using hyperlinks).

The HTML "Meta" Tag

HTML allows to insert meta tags (as many as you like) into the head of an HTML document. Basically it seems that people mostly use the following name attribute values:

• "robots": (to inhibit robot indexing)

<meta name="robots" content="noindex">

• "description": used by search engines

<meta name="description" content="this is a page about metadata">

• "keywords" also used by search engines

<meta name="keywords" content="metadata, dublin core, LOM">

Meta anything=" ". You may use the Dublin Core taxonomy for instance, but this is only useful if you know that a specialized search engine will use it.

Note: The Meta Http-Equiv="..." attribute is used to insert HTTP directives.

References

• Clay Shirky (2003). The Semantic Web, Syllogism, and Worldview, HTML

• Powell, Andy (2003). Expressing Dublin Core in HTML/XHTML meta and link elements, Dublin Core Metadata Initiative, [1] , retrieved 13:18, 12 April 2007 (MEST).