This allows to use the variable where ever you need a content node (for passing to a tag for example). The map should support all properties of the Content object. This allows expressions like:

<cms:out nodeDataName="link" var="uuid" />

<cms:setNode var="paragraph"/>

<cms:setNode uuid="${uuid}" var="other"/>
<cms:setNode uuid="${paragraph.link}" var="other2"/>

-${other.title}<br/>
-${other.name}<br/>
-${other.metaData.modificationDate}<br/>
-${other.uuid}<br/>

<cms:out contentNode="${other}" nodeDataName="theField" />