XML is the acronym for Extensible Markup Language, which means in Portuguese Extensible Generic Markup Language. It is a recommendation to generate markup languages for special needs. XML is capable of describing different types of data, and its main purpose is the ease of sharing information over the Internet.
XML-based languages include XHTML (format for web pages), SDMX, SMIL, MathML (format for mathematical expressions), NCL, XBRL, XSIL and SVG (vector graphic format). The main characteristic of XML is to create a single infrastructure for several languages.
XML is a simple technology that has around it other technologies that complement it and make it much bigger and with much broader possibilities. XML represents a different way of doing things, whose main new feature is that it allows sharing. XML also allows the programmer and supports to devote their efforts to the important tasks when working with the data, as some laborious tasks such as validating these or traversing the structures are in charge of the language and are specified by the standard.