XML (Extensible Markup Language)

Definition – What is XML (Extensible Markup Language)

XML generally refers Extensible Markup Language is a Data serialization technology and Markup language basically used widely in application development field and web internet services. XML is very reliable because of its simple structure that is both human and machine-readable.

Many web technologies use XML as  Data serialization tools including Atom, SVG, SOAP even XHTML. XML has a strong support of Unicode that’s why it supports multiple languages. XML also can be used as a file configuration tools, for example, Microsoft .NET framework uses XML as file configuration tools.

XML Media Type

Nowadays XML is very common on the web and widely known. Every developer and programmer should learn this markup language. XML has the common media type of application/xml and text/xml. Many times in a specific domain XML use media type like image/svg+xml.


XML Example File

The great feature of XML is customized uses. User or developer can define their own tag to markup a document. Here a simple example of XML that refers to an email data from Alexa to David.

<body>Hey David meet me today. Don't forget me this weekend!</body>


Characters: XML is basically built in the string and the strings are sets of characteristics. It has a strong support of Unicode and every almost every Unicode character can be shown an XML file.
Declaration: Commonly all XML file begins with a declaration that says that describes some information and retrieve the core syntax from the XML library. Most of the time the XML declaration defined as <?xml version="1.0" encoding="UTF-8"?>.
Tag: Like all other markup language XML tag begins with <and ends with > . <section>  is a start tag and </section>is the end tag. Unlike other markup languages, such as HTML you can define your own tag that can not be done in HTML. For instance, <yourtag> element </yourtag> is valid in XML but not valid in HTML. HTML has a predefined tag list.