Metadata is used to identify the data relevant to X3D scenes and shapes, enabling the possibility of further correlation, discovery and Web-based mashups to occur.

Metadata (book with question mark)

Metadata is about forms of data relating to other data. For example, metadata can provide a variety of information regarding a document such as author, date revised, relevant key words, etc. As another example, metadata might annotate X3D CAD geometry to provide key references such as part numbers, documentation references, inventory links, etc.

Simple name=value paired information can be provided in document <head> and <meta> tags, just like in HTML. Furthermore, typed metadata information can annotate any X3D node, either for use offline or for queries within an active scene graph at run time. X3D metadata nodes include MetadataBoolean, MetadataDouble, MetadataFloat, MetadataInteger, MetadataString, and MetadataSet (a set holder which contains a collection of other X3D Metadata nodes).

The supporting Chapter 15 Metadata Information from X3D for Web Authors is available online via X3dGraphics.com. Also available:

Library card catalogs provide metadata