XInculde 1.0 provides a processing model and syntax for general purpose inclusion. Inclusion is accomplished by merging a number of XML information sets into a single composite infoset. Specification of the XML documents (infosets) to be merged and control over the merging process is expressed in XML-friendly syntax (elements, attributes, URI references).
Specification: http://www.w3.org/TR/xinclude/ (W3C)
XML Events 1.0
XML Events 1.0 provides XML languages with the ability to uniformly integrate event listeners and associated event handlers with Document Object Model (DOM) Level 2 event interfaces. The result is to provide an interoperable way of associating behaviors with document-level markup.
Specification: http://www.w3.org/TR/2003/REC-xml-events-20031014/ (W3C)
XML Schema 1.1 Part 2: Datatypes
"XML Schema 1.1 Part 2: Datatypes" defines facilities for defining datatypes to be used in XML Schemas as well as other XML specifications. The datatype language, which is itself represented in XML 1.0, provides a superset of the capabilities found in XML 1.0 document type definitions (DTDs) for specifying datatypes on elements and attributes.
Specification: http://www.w3.org/TR/xmlschema11-2/ (W3C)
Synchronized Multimedia Integration Language (SMIL) 3.0
SMIL 3.0 defines an XML-based language that allows authors to write interactive multimedia presentations. Using SMIL, an author may describe the temporal behaviour of a multimedia presentation, associate hyperlinks with media objects and describe the layout of the presentation on a screen.
Specification: http://www.w3.org/TR/SMIL3/ (W3C)
Remote Events for XML (REX) 1.0 (in development)
Remote Events for XML (REX) 1.0 is an XML grammar for representing events as they are defined in DOM 3 Events, primarily but not exclusively for purposes of transmission. It enables one endpoint to interact remotely with another endpoint holding a DOM representation by sending it DOM Events as if they had occurred directly at the same location.
Specification: http://www.w3.org/TR/rex/ (W3C)
XBL 2.0 (in development)
The XML Binding Language (XBL) describes the ability to associate elements in a document with script, event handlers, CSS, and more complex content models, which can be stored in another document. This can be used to re-order and wrap content so that, for instance, simple HTML or XHTML markup can have complex CSS styles applied without requiring that the markup be polluted with multiple semantically neutral div elements.
Specification: http://www.w3.org/TR/xbl/ (W3C)