Difference between XSD and XSLT.

Lets Start with the definitions first:

XML: XML is nothing but a NODED string.

XSLT is a declarative programming language, you write an XSLT stylesheet to transform XML to HTML or XML or plain text.

XSD is a schema language, you use it to define the possible structure and contents of an XML format. A validating parser can then check whether an XML instance document conforms to an XSD schema or a set of schemas.

Consider the below code to know more about the format of XML, XSD and XSLT.

Below is an example of a XML file: (person.xml)

<Persons xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <Person>
        <FirstName id="1">Kavita</FirstName>
        <LastName>Khandhadia</LastName>
    </Person>
    <Person>
        <FirstName id="2">Nishant</FirstName>
        <LastName>Khandhadia</LastName>
    </Person>
</Persons>

The above XML has been derived from the below schema file ( XSD File)

 Now for above example there can be an XSD file like this.

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified">
  <xs:element name="Persons">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="Person"/>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="Person">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="FirstName"/>
        <xs:element ref="LastName"/>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="FirstName">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:NCName">
          <xs:attribute name="id" use="required" type="xs:integer"/>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="LastName" type="xs:NCName"/>
</xs:schema>

Now supppose in some case, instead of above person.xml, u want customer.xml which
 takes data from person.xml but has totally different structure ..may be like this.


<?xml version='1.0' ?>
<Cusotmers>
    <Customer>Kavita</Customer>
    <Customer>Nishant</Customer>
</Cusotmers>

In such cases we use XSLT file. to transform person.xml to customer.xml(Above) - We use XSLT.

 <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

<xsl:template match="/">
    <Cusotmers>
    <xsl:for-each select="Persons/Person">    
        <Customer><xsl:value-of select="FirstName"/></Customer>
        </xsl:for-each>
    </Cusotmers>
</xsl:template>

</xsl:stylesheet>

In this way, we have