§ 8.1 RDFa

 has support for representing and generating RDFa metadata in  documents. The core attributes property, rel, rev, about resource, typeof and content are included. Provision is also made for about and resource to be specified using -style labels, or plain xml id’s.

The default set of vocabularies is specified in HTML Role Vocabulary, and the associated set of prefixes are predefined.

It is intended that the support will be extended to automatically generate RDFa data from the implied semantics of  markup; the idea would be not to inadvertently override any explicitly provided metadata supplied by one of the following packages.

The hyperref package

The hyperref and hyperxmp packages provide a means to specify metadata which will be embedded in the generated pdf file;  converts that data to RDFa in its generated XML.

The lxRDFa package

There is also a -specific package, lxRDFa, which provides several commands for annotating the generated XML. The most powerful of which is \lxRDFa which allows you to specify any set or subset of RDFa attributes on the current XML element and thus take advantage of the arbitrary shorthands, chaining and partial triples that RDFa allows. Correspondingly, you are must beware of clashes or unintended changes to the set of triples generated by explicit and hidden RDFa data.