XML stands for “Extensible Markup Language” and is a text file having information according to a given structure. It is a meta-language for defining markup languages for the representation of information to be exchanged over the Internet.
XML is the successor to SGML (standard generalized markup language) and HTML (Hypertext markup language) for representing semi-structured documents.
Example of XML:
<?xml version=1.0″ standalone=”yes” ?>
– <Site Name=”whatwhenwhowhy” URL=”www.whatwhenwhowhy.com”>
- It is a standard which is known internationally
- It does not belong to any company and is available for all
- It enables effective use of Internet for different terminals.
Advantages of XML:
- Easily processable
- Radically separates the content and presentation format
- Designed for any language and alphabet. (Encoding)
Characteristics of XML:
- XML is a subset of SGML that incorporates the three most important characteristics of this:
- Not content oriented presentation.
- The labels are defined to create documents, do not have a predetermined meaning.
- It is not a substitute for HTML.
- There is no generic XML viewer.
- Components of an XML document
In an XML document below are the following seen:
- Elements: logic part marking, is represented by a text string (data) enclosed labels. There may be empty elements (<br/>).
- Instructions: The instructions in XML starts with <? And they end up?>.
- Comments: Information that is not part of the document. They start with <! – And end by ->.
- Type declarations: It Specifies information about the document: <! DOCTYPE SYSTEM person “persona.dtd”>
- CDATA Sections: This is a character set that cannot be interpreted by the processor: <! [CDATA [Here you can put any character, such as <, &,>, … without being interpreted as marking]]>