Use apply-templates without attributes to process all child nodes of the current context-node.
<xsl:apply-templates/>
Use apply-templates with a select attribute to process nodes and child-nodes specified by the select attribute.
<xsl:apply-templates select="*/@test"/>
Use apply-templates with the mode attribute to process all selected nodes with templates that have the same mode attribute defined.
<xsl:apply-templates mode="test"/>
<xsl:apply-templates select="*/@test" mode="test"/>