If your site has identical or similar content that's accessible through multiple URLs, the canonical tag helps you to identify the "primary" page where the content resides. This will give you greater control over the URL returned in search results. It also helps to make sure that properties such as link popularity are consolidated to your preferred page versions.

nonical tags are used to avoid issues like duplicate content in case there are multiple pages with similar content or multiple paths to the same page.

See more info here: http://googlewebmastercentral.blogspot.com/2009/02/specify-your-canonical.html

List of Websites

• The Holy Trinity Store
• 800-espresso.com
• AffordableLamps.com
• AtlasPhones.com