you can study xls language in the below link :

http://www.w3schools.com/xsl/xsl_languages.asp

CSS = Style Sheets for HTML

XSL = Style Sheets for XML

think the xml like html and xsl like css .

for example:

xml:

John Doe 10.99 Mary Jones 15.99 Garry Po 20.99

xsl:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:msxsl="urn:schemas-microsoft-com:xslt" exclude-result-prefixes="msxsl"

            <table border="1">  
                <tr bgcolor="#9acd32">  
                    <th>Title</th>  
                    <th>Artist</th>  
                </tr>  
                <xsl:for-each select="collection/book">  
                    <tr>  
                        <td>  
                            <xsl:value-of select="author"/>  
                        </td>  
                        <td>  
                            <xsl:value-of select="price"/>  
                        </td>  
                    </tr>  
                </xsl:for-each>  
            </table>  
</xsl:template>

in xml we need to set xsl file link just like html use css link .

you can use

response.redirect ("xmlfile") or use iframe