Extensible Markup Language

XML Introduction

Extensible Markup Language

Xml (Extensible Markup Language)

XML stands for extensible markup language, XML is sued to provide on environment to create a cross platform compatibility, cross platform it is not a specific to only software and hardware and any other computer architecture, XML is also Called as mother language by uing which we can create VML ( Vector Markup Language) and MML ( Mathematical Markup Language) XML namely used to store the data and described the data.

It is used to store the data permanently as same as like data base.

XML is used to provide an instruction to install a software.

XML is used to configure the resources for ever web application.

XML is used to create other markup language.

XML is used to transfer the data between incompatible types it means we can used XML document data in any language.

Using XML we can create our own tags.

Difference between XML and HTML.


  1. XML is used to store the data and describe the data.
  2. XML contains a user define tags.
  3. It is not a error free language i.e it is encounter any errors then it will show the error on web browser.
  4. It is a case sensitive.
  5. It can support only proper nesting.
  6. XML defines structure for the data.


  1. It is used to create web page.
  2. HTML contains predefined tags.
  3. It is not a case sensitive.
  4. It is a error free language i.e. it is encounter an error then it will not and show any error information.
  5. HTML support proper nesting and improper nesting.
  6. HTML apply some slice on the data.

XML document contain the root tags it must be presented once time.

Element tags are nested

XML document consist of one or more elements logically related collection of information to the complete documentation is document entity.

The XML document can be broken into smallest part. The document can be easily managed.

XML tags contains the child and attribute or both.

XML document can’t store the image type of information is generate stored in separate file.


Rules of XML

  1. It is a case sensitive.
  2. The elements are start and end which tag.
  3. Elements in tag properly and nested.
  4. XML document must contain root tag it must be presented once time.
  5. The XML document consist one or more elements that have logically related collection of information the complete document called document entities.
  6. The complete XML document broken into smallest part of entity the document become easily manageable.
  7. Xml document cannot store image type of information is generally store in separate file.
  8. XML Tags will contain child tag or attributes or both.
  9. The XML tag contains attributes then it’s value must be specified between “ “ or ‘ ‘
  10. XML tag may be entity.
  11. XML tag must be start with

<? XML version =”1.0” encoding =”UTF-8” standalone =”yes”>


<? XML version =”1.0” >

XML file may not contain character that are reserved

Elements and Attributes in XML

The basic entity is element the element are used for designing the tags, the element logically consist of opening and closing tags mostly one element is used to design a single tag.

The Attributes are generally used to specify the Value or element specified with “ “ or ‘ ‘.

Rules with declaring Element

  1. XML element may be the combination of digits or alphabet or both
  2. It should not start with digits.
  3. It should not contain special character.
  4. ment name should contain space
  5. It contain multiple root separate with hypen or underscore.

Well form of XML

XML element specify both XML document preparation of an element naming root then it is called well form XML document.



< Student >

<Course> computer science</Course>

<Name> Aradhya </Name>


Reason to Avoid Attributes

  1. Attributes will not show any hearchey.
  2. Attitude will not show amount of data values.
  3. Attribute will not contain multiple values.
  4. It is not possible to write sum attribute for multiple times it means cannot expand the Attributes.
  5. It is described to read by processing XML document.

XML Schema

It is used to define the structure for an XML document, Xml schema return in XML.

It is more powerful and reach in functionality it supports data type it supports name, spaces we can also we can also create user defined datatypes based on standard datatypes.

Elements in XML Schema

In XML Schema we can create following two types of elements

  1. Simple
  2. Complex

Simple :

If a XML element contains only data it is found simple elements it does not Contains attributes or child’s


It is an XML element contains child element or Attributes or both is called complex elements.