The HTMLAreaElement.rel property reflects the rel attribute. It is a DOMString containing a space-separated list of link types indicating the relationship between the resource represented by the <a> element and the current document.
Syntax
var relstr = areaElt.rel;
areaElt.rel = relstr;
Example
var areas = document.getElementsByTagName("area");
var length = areas.length;
for (var i = 0; i < length; i++) {
alert(areas[i]);
}