Is a text-based metalanguage. It was created to separate the properties like strength and flexibility of SGML from the complexity.
The abbreviation stands for "Extensible Markup Language", it enables data or documents to be presented in such a way that they can be processed and exchanged as often as possible, especially over the Internet.
Mainly, XML is based on a strict separation between layout, content and structure.
The many possibilities of application are offered above all by the openness of XML.
A major advantage is that XML, in contrast to HTML, also allows the structure of data to be described.