Summary of addressing elements

This topic contains a table of DITA elements that may be used to link to or address other items. The table describes how and why each element uses the addressing mechanism, rather than defining the element itself.

Table 1. DITA addressing elements
Base element type	Description and notes
topicref	Establishes a relationship between the containing map and another map, DITA topic, or non-DITA resource when @href or @keyref is specified. When @processing-role is "resource-only", establishes a dependency on the target resource but does not contribute to the navigation tree. May establish additional relationships between the referenced resource and other resources in the navigation hierarchy as determined by the values of the @collection-type attribute. By default, these additional relationships are bi-directional. The directionality of additional relationships can be controlled using the @linking attribute.
reltable	Establishes relations of a specific type (as defined by the relationship table) among topicref-linked resources where each row in the table establishes a single set of relationships among the topicref-linked resources in each cell of the row. Relationships defined in relationship tables are outside of any navigation structure defined by the map.
navref	Establishes a map-to-map relationship where the integration of the referenced map's navigation structure is deferred. The referenced map is processed independently from the referencing map and does not contribute to the referencing map's key space.
link	Establishes a link from its containing topic to another resource. Any <link> element within a topic can be functionally replaced by the equivalent link defined in a relationship table. Likewise, topic-to-topic links defined by relationship tables can be replaced by the equivalent set of <link> elements in the topics involved.
xref	Establishes a navigation link from a topic's abstract or body to another DITA element or non-DITA resource.
image	Links to an image for display at the point of reference.
object	Links to a media object for display at the point of reference.
longdescref	Links to a long description for an image or object. Can be used in place of the @longdescref attribute on the parent image or object element.
longquoteref	Links to the source of a long quotation. Used in place of the @href or @keyref attribute on <lq> and enables use of all the normal link-controlling attributes.
data-about	Establishes an explicit relationship between one or more <data> elements and the DITA element or non-DITA resource to which the data applies.
Elements that take @keyref but not @href	Elements that take @keyref but not @href establish navigation links to the referenced DITA element or non-DITA resource when @keyref is specified and the key is bound to a topic, map, or non-DITA resource. If the linking element has empty content and the key definition has a matching subelement in its <topicmeta>, establishes a use-by-reference relationship to the matchin element in the key definition. Includes <ph>, <cite>, <keyword>, and <term>.
imagemap (utilities domain)	Enables linking from defined areas overlaid on a graphic. Modeled on the HTML image map facility.
author	May link to a resource that represents the author in some way, such as a biographical topic or image.
data	May link to a resource that represents the metadata value in some way.
fragref (programming domain)	Links to a syntax definition fragment.
lq	May link to the source of the quotation.
publisher	May link to a resource that represents the publisher in some way, such as the Publisher's Web site or a publisher description topic.
source	May link to a description of the source for the topic to which the <source> element applies.
synnoteref (programming domain)	May link to a syntax note.
fn	Establishes a relationship between the content within which the footnote appears and the note itself, such that the footnote is an annotation of the content.

2.1.3.4.4 Summary of addressing elements