CSS (Cascading Style Sheets)
too limited to cover complexity of DocBook
are used to define visual appearance of DocBook in visual XML editors
W3C recommendation
XSL (Extensible Stylesheet Language)
XSLT – describes transformation from XML document to XML, HTML or plain text
XSL FO (formatting objects) – “typographical quality” formatting for printed media (PDF, PostScript, RTF)
W3C recommendation
DSSSL (Document Style Semantics and Specification Language)
originally developed for SGML, can be used with XML as well
transformation to HTML, print output
ISO standard