XML Base

XLink describes links between resources. One of the stated requirements on XLink is to support HTML linking constructs in a generic way. The HTML BASE element is one such construct which the XLink Working Group has considered. BASE allows authors to explicitly specify a document's base URI for the purpose of resolving relative URIs in links to external images, applets, form-processing programs, style sheets, and so on.

XML Base describes a mechanism for providing base URI services to XLink, but as a modular specification so that other XML applications benefiting from additional control over relative URIs (but not built upon) XLink can also make use of it. The syntax consists of a single XML attribute named xml:base.

The deployment of XML Base is through normative references by new specifications, for example XLink and the XML Infoset. Applications and specifications built upon these technologies will natively support XML Base.

XML Base became a W3C Resommendation on June 27, 2001.