Canonical 1.0 Features- Print canonical tag to your html header by Canonical plugin.- Import new canonical component to use with Canonical component.- Update canonical component setting by Import feature.Usage : login to backend and then go to Components->Canonical->components page and import canonical xml file for your favorite component.Component Support- Joomla Content com_content- K2 com_k2- Jomsocial  com_community- FLEXIContent com_flexicontent* you can request xml element for your component

 

www.cmsplugin.com/home/item/9-canonical-print-canonical-tag-to-your-html-header.html

what is a Canonical URL?
Lots of discussion about canonicalization and canonical URLs lately. I’ve discussed URLs and URL structure a few times in the past. We thought that we would help illustrate the idea of canonical URLs. From an SEO point of view here is the definition of a canonical URL:
Canonical URL: the search engine friendly URL that you want the search engines to treat as authoritative. In other words, a canonical URL is the URL that you want visitors to see.
ask.enquiro.com/2009/what-is-a-canonical-url/
googlewebmastercentral.blogspot.com/2009/02/specify-your-canonical.html