Extensible Markup Language
- A highly flexible syntax that allows you to describe virtually any kind of information, from a simple recipe to a complex database. It uses tags that are similar to the tags in HTML to define document components. Unlike HTML, it allows users to specify their own tag names (hence the term 'extensible').
An XML document --in conjunction with a style sheet or a conventional HTML page-- can be easily displayed in a web browser. Because an XML document structures and labels the information it contains, the browser can find, extract, sort, filter, arrange, and manipulate that information in highly flexible ways.
XML's flexibility has led many industry groups and standards bodies to produce a variety of dialects to suite the needs of their applications. VoiceXML and CCXML are two examples that are of particular interest to the call center industry, but there are hundreds of standard dialects covering everything from EDI derivatives to database queries.
XML is also the principle transfer language used to implement web services over SOA. It is primarily used in standards such as SOAP to define the structure of communications between web service providers and clients.