Canonical Link Relation

File Format
Name	Canonical Link Relation
Ontology	Electronic File Formats Web Canonical Link Relation

The Canonical Link Relation is a standard way to use the HTML <link> element, or the HTTP "Link" header, to suggest the best URL to use when multiple substantially-identical documents exist.

Links

• RFC 6596: The Canonical Link Relation
• Wikipedia article
• Google Webmaster Tools: About rel="canonical"