This chapter surveys several additional XML-related technologies. Full documentation of each standard is beyond the scope of this reference, either because its use is limited or because its nature is not directly related to the web.
XHTML — a stricter, XML-well-formed version of HTML.
XSL-FO — a markup language for formatting XML data for output to screen, paper, or other media.
XBRL — an XML-based standard for reporting business information.
XProc — a language for describing a pipeline of operations performed on XML documents.
XKMS — a specification for managing the public key infrastructure (PKI) used to secure communication between applications.
appML — an HTML extension for building web-based applications.