XML (eXtensible Markup Language) is a textual (Unicode ISO/IEC 10646, see www.unicode.org) mark-up language for describing the structure and the meaning of data.
XML can, in theory, be read by both men and machine. Nevertheless, most XML is devised for processing by computers. It is an open standard, defined by the World Wide Web Consortium (see www.w3c.org) and is suitable for use across all sorts of different computing platforms.
Conversion of files to XML is a distinct type of migration technique. However, XML is also considered a sustainable file format for archiving and interoperability. It is therefore considered as a preservation approach in its own right.