XML stands for EXtensible Markup Language. XML is a markup language for documents containing structured information. XML is much like HTML, but in a more descriptive way. HTML is about displaying information, while XML is about describing information.

Structured information contains both content (words, pictures, etc.) and some indication of what role that content plays (for example, content in a section heading has a different meaning from content in a table celle, etc.). Almost all documents have some structure.

A markup language is a mechanism to identify structures in a document. The XML specification defines a standard way to add markup to documents.

The major difference between XML and other document formats is that XML seprates the actual document content from the document styles or views. This means the same XML file is used for multimedia publishing (single source publishing).

Advantages of XML (some of them)

• With XML, you store the data once and then render that content for different viewers or devices based on style sheet processing.
• XML defines the type of information contained in a document, making it easier to return useful results when searching the Web
• XML provides portable and structured information types for display on pervasive (wireless) computing devices such as PDAs, cellular phones, and others
• Extendable. Create your own tags (or use tags created by others) that use the native language of your domain, have the attributes you need, and make sense to you and your users.

XML facts

• XML is a W3C standard
• Standard Generalized Markup Language (SGML) is the ISO standard on which all XML documents are based upon.
• XML is a open format
• XML can include every types of data (text, graphics, video, sound, Java applets, ActiveX, etc.)

 More information about XML

• www.w3.org/XML/
• www.xml.com/