Declarative markup languages

LaTeX ( or , to rhyme with "blech"), often stylized as '''''', is a software system for typesetting documents, based on the TeX typesetting system. LaTeX provides a high-level, descriptive markup language to use TeX more easily: TeX handles the document layout, while LaTeX handles the content side for document processing. Because the plain TeX formatting commands are elementary, it provides authors with ready-made commands for formatting and layout requirements such as chapter headings, footnotes, cross-references and bibliographies.

programming language

XML-based markup language for multimedia presentations

XML Binding Language (XBL) is an XML-based markup language for altering the behavior of XUL widgets. It was devised at Netscape in the late 1990s as an extension of XUL.

REVTeX, sometimes stylized as '''''', is a collection of LaTeX macros which is maintained and distributed by the American Physical Society with auxiliary files and a user support guide, as part of a "REVTeX toolbox." REVTeX is used to submit papers to journals published by the American Physical Society (APS), the American Institute of Physics (AIP), and the Optical Society of America (OSA). REVTeX is accepted by a few other technical publishers as well.