Sometimes RDF documents can scale to be rather large and unweildy, this is partly caused by the placement of long URIs for the RDF nodes.
Fortunately this problem can be overcome by using CURIEs in place of the URIs.
Short for Compact URI, CURIEs abbreviate URIs!
Found a wicked example and explanation over on wikipedia.
As explained in the article, and also the W3C's working draft for CURIE Syntax, it's also handy to note that to avoid disambiguation between URIs and CURIEs, such collisions and confusion can be avoided by wrapping CURIEs in square brackets;
<html xmlns:ex="http://www.example.org/">
<head>...</head>
<body>
<p rel="foaf:homePage" about="[ex:home.html]">home</p>
</body>
</html>