Unit – 4
1. XML BASICS & INTRODUCTION :
XML is a software- and hardware-independent tool for storing and transporting data.
What is XML?
• XML stands for eXtensible Markup Language
• XML is a markup language much like HTML
• XML was designed to store and transport data
• XML was designed to be self-descriptive
• XML is a W3C Recommendation
XML and HTML were designed with different goals:
• XML was designed to carry data - with focus on what data is
• HTML was designed to display data - with focus on how data looks
• XML tags are not predefined like HTML tags are
XML Does Not Use Predefined Tags
• The XML language has no predefined tags.
• The tags in the example above (like <to> and <from>) are not defined in any XML
standard. These tags are "invented" by the author of the XML document.
• HTML works with predefined tags like <p>, <h1>, <table>, etc.
• With XML, the author must define both the tags and the document structure.
Example
<note>
<to>Tove</to>
<from>Jani</from>
<heading>Reminder</heading>
<body>Don't forget me this weekend!</body>
</note>
The XML above is quite self-descriptive:
▪ It has sender information.
▪ It has receiver information
▪ It has a heading
▪ It has a message body.
But still, the XML above does not DO anything. XML is just information wrapped in
, 2. NEED FOR XML
• XML was designed to store and transport data.
• XML was designed to be both human- and machine-readable.
• XML tags identify the data and are used to store and organize the data, rather than
specifying how to display it like HTML tags, which are used to display the data.Three
important characteristics of XML
• XML is extensible
• XML allows you to create your own self-descriptive tags, or language, that suits your
application.XML carries the data, does not present it
• XML allows you to store the data irrespective of how it will be presented.
• XML is a public standard: XML was developed by an organization called the World
Wide Web Consortium (W3C) and is available as an open standard.
• XML Usage XML can work behind the scene to simplify the creation of HTML
documents for large web sites.XML can be used to exchange the information between
organizations and stems
• XML can be used for offloading and reloading of databases.XML can be used to store
and arrange the data, which can customize your data handling needs
• XML can easily be merged with style sheets to create almost any desired
output.Virtually, any type of data can be expressed as an XML document.
XML - Syntax
<?xml version="1.0" encoding="UTF-8"?>
XML Declaration<?xml version="1.0" encoding="UTF-8"?>
3. WORKIN WITH AN XML DOCUMENT:
• Working with XML files is relatively simple, even for a beginner. A couple of
different methods for opening an XML file are to open the file and edit with a text
editor or to open and view the file with a web browser.
• The steps for opening an XML file to view in a web browser include
• Open your default web browser
• Double-click on the XML file and it should open in your browser
• If it does not open, right-click on the file to find a list of options for opening it with
other programs
• Now you will be able to select your web browser from the list of programs.
1. XML BASICS & INTRODUCTION :
XML is a software- and hardware-independent tool for storing and transporting data.
What is XML?
• XML stands for eXtensible Markup Language
• XML is a markup language much like HTML
• XML was designed to store and transport data
• XML was designed to be self-descriptive
• XML is a W3C Recommendation
XML and HTML were designed with different goals:
• XML was designed to carry data - with focus on what data is
• HTML was designed to display data - with focus on how data looks
• XML tags are not predefined like HTML tags are
XML Does Not Use Predefined Tags
• The XML language has no predefined tags.
• The tags in the example above (like <to> and <from>) are not defined in any XML
standard. These tags are "invented" by the author of the XML document.
• HTML works with predefined tags like <p>, <h1>, <table>, etc.
• With XML, the author must define both the tags and the document structure.
Example
<note>
<to>Tove</to>
<from>Jani</from>
<heading>Reminder</heading>
<body>Don't forget me this weekend!</body>
</note>
The XML above is quite self-descriptive:
▪ It has sender information.
▪ It has receiver information
▪ It has a heading
▪ It has a message body.
But still, the XML above does not DO anything. XML is just information wrapped in
, 2. NEED FOR XML
• XML was designed to store and transport data.
• XML was designed to be both human- and machine-readable.
• XML tags identify the data and are used to store and organize the data, rather than
specifying how to display it like HTML tags, which are used to display the data.Three
important characteristics of XML
• XML is extensible
• XML allows you to create your own self-descriptive tags, or language, that suits your
application.XML carries the data, does not present it
• XML allows you to store the data irrespective of how it will be presented.
• XML is a public standard: XML was developed by an organization called the World
Wide Web Consortium (W3C) and is available as an open standard.
• XML Usage XML can work behind the scene to simplify the creation of HTML
documents for large web sites.XML can be used to exchange the information between
organizations and stems
• XML can be used for offloading and reloading of databases.XML can be used to store
and arrange the data, which can customize your data handling needs
• XML can easily be merged with style sheets to create almost any desired
output.Virtually, any type of data can be expressed as an XML document.
XML - Syntax
<?xml version="1.0" encoding="UTF-8"?>
XML Declaration<?xml version="1.0" encoding="UTF-8"?>
3. WORKIN WITH AN XML DOCUMENT:
• Working with XML files is relatively simple, even for a beginner. A couple of
different methods for opening an XML file are to open the file and edit with a text
editor or to open and view the file with a web browser.
• The steps for opening an XML file to view in a web browser include
• Open your default web browser
• Double-click on the XML file and it should open in your browser
• If it does not open, right-click on the file to find a list of options for opening it with
other programs
• Now you will be able to select your web browser from the list of programs.
