Authoring Match Patterns

The match attribute on the <xsl:template> element contains a pattern expression. The syntax is the same as that used to select nodes with <xsl:for-each>, <xsl:value-of>, and <xsl:apply-templates> elements. However, the pattern is used in quite a different way.

http://msdn.microsoft.com/library/en-us/xmlsdk30/htm/xmconauthoringmatchpatterns.asp?frame=true