HyTime, the Hypermedia/Time-based Structuring Language, is a markup language that is an "application" of SGML. HyTime defines a set of hypertext-oriented element types that, in effect, supplement SGML and allow SGML document authors to build hypertext and multimedia presentations in a standardized way. HyTime is an international standard published by the ISO and IEC. The first edition was published in 1992, and the second edition was published in 1997. Some of the concepts formalized in HyTime were later incorporated into HTML and XML.