???-
root'p??
The relationship vocabulary can be used to describe relationships with the people linked from a web page. This is particularly useful for blogrolls or contact lists but can be used with any type of link. The HTML codeaD element provides two attributes, ahref7http://www.w3.org/TR/html401/struct/links.html#adef-relrel and revj, that can be used to specify the relationship. Both rel
and rev?? take a space separated list of keywords as their value. To use a term from the relationship vocabulary just drop the Fhttp://purl.org/vocab/relationship/X namespace to leave the property name, e.g. Xhttp://purl.org/vocab/relationship/worksWith would become worksWithH which can be added as the value of rel or rev.
dl
dt
rel
dd
The relv attribute specifies a relationship that the author of the emlinkedB page has with the author of the linkingL page.
For example:
prespan
classelem<aattrhref="attrVal0http://example.com/boats" attr highlightrel="attrValchildOf"elem>text(The boat we restoredelem
"</a>
HThis link states that the author of 0http://example.com/boatsZ is a child of the author of the html above.
rev
The revv attribute specifies a relationship that the author of the linkingF page has with the author of the linkedH page. The example here is:
elem<aattrhref="attrVal0http://example.com/boats" attr highlightrev="attrValchildOf"elem>text(The boat we restoredelem
"</a>
??In this case the meaning of the link is reversed: the author of the html above is a child of the author of 0http://example.com/boats.
??The HTML and XHTML recommendations require an HTML document to declare a custom profile if it uses any non-standard rel or revB types. This is done by adding a profile6 attribute with a value of Fhttp://purl.org/vocab/relationship/& to the document's head element.
?? <head profile="http://purl.org/vocab/relationship/">
<title>People I Know</title>
</head>
h3 Complete Example
?@ <html profile="http://purl.org/vocab/relationship/">
<head>
<title>People I Know</title>
</head>
<body>
<p>Here are the people I know:</p>
<ul>
<li><a href="http://example.com/~freddy" rel="closeFriendOf">Freddy (he's cool!)</a></li>
<li><a href="http://frooble.com/" rel="mentorOf">Jimbo</a></li>
<li><a href="http://mmmm.com/klm" rel="friendOf">Katie</a></li>
<li><a href="http://example.com/~omah" rel="worksWith">Omah (does the coding)</a></li>
<li><a href="http://example.com/~jason" rev="closeFriendOf employedBy">Jason, my henchman</a></li>
</ul>
</body>
</html>
$RDF Interpretation
?JCustom parsers that extract RDF from (X)HTML can use the relationships expressed in the links to infer the
equivilent RDF triples. It should be remembered that the relationship is between the authors of the pages not between
the pages themselves. Given the following link on a document at <http://example.com/mypage.html:
elem<aattrhref="attrVal0http://example.com/boats" attr highlightrel="attrValchildOf"elem>text(The boat we restoredelem
"</a>
<a suggested RDF extraction is:
?? <foaf:Person>
<foaf:maker rdf:resource="http://example.com/boats"/>
<rel:childOf>
<foaf:Person>
<foaf:maker rdf:resource="http://example.com/mypage.html"/>
</foaf:Person>
</rel:childOf>
</foaf:Person>