Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding a document in a format that is human-readable and machine-readable. Defined in XML 1.0 specification produced by W3C, and several other related specifications, all free open standards.
The design goals of XML emphasized simplicity and usability, General, over the Internet. This is a textual data format, with strong support via Unicode for the languages of the world. Although the design of XML document, it focuses on the widely used for arbitrary data structures, such as in web services.
Many application programming interfaces (APIs) has developed a software developer using the process XML data, and some systems there is a scheme to assist in the definition of XML-based language.
2009, hundreds of XML-based languages have been developed, including RSS, Atom, SOAP, and XHTML. XML-based format has become the default for many Office productivity tools, including Microsoft Office (Office Open XML), OpenOffice.org (OpenDocument), and Apple’s iWork.8 XML is also used as the primary language for communication protocols, such as XMPP.