The XML style sheet in Table 4-3 introduces the if statement as well as the ability to sort elements.
The if statement executes code based on the evaluation of the condition given in the "test" attribute,e.g.
<xsl:if test="population >= 10000">
<xsl:if test="population < 10000">
Possible expressions for the condition are
equality of two values
inequality of two values
less than or equal
greater than or equal
Output can be sorted based on the value of the select attribute of the <xsl:sort> element.