Posted by David • Mar 18th, 2011 9:59:54 pm - Subscribe | Mood: Good | Music: Sax Man Serenade
Article explains how Canonical Links Help Transfer Page Rank & Link Juice.
What are Canonical Tags?
Canonical spelled CON-AUT-ICAL is simply rel="canonical" tag that you place in your meta keywords area or near your meta description tags that defines the url that is supposed to be where the content of the page resides.
So if you have a page that is domain.com/product-abc and if you have people sending in with paramater tag you can end up with multiple URL's having that same exact contact being displayed you can use the ref="canonical" tag to tell all those other version of the URL that NO this is the right version of the URL. This is that we want indexed by the search engines.
There are many ways a search engine can see a page, and there are many ways that a person can link to you on a certain page. Another example is.
Well you get the hint. All of these URL's are unique, but all point to the same content. Using the rel="canonical" tag can save you the grief of search engines not indexing you the way you would like to be indexed. For the most part search engines have gotten smarter and will evaluate your website as being domain.com or www.domain.com but I would advise you as an SEO to play it safe and add the canonical tag inside of your pages.
Confused? Give this slide a try, perhaps it will better explain visually for you
So all and all canonical tags are great to have on your site on every page that you have the main source for that content. Every where else you may have duplicate content of the same thing make sure that canonical has point to the original.
Keep in mind that doing rel="canonical" from one domain to another does work, and in that case if it is passing link juice. That makes this whole topic very interesting.
How How Canonical Links Help Transfer Page Rank & Link Juice
Well most of you are probably asking yourself, well can a canonical tag transfer link juice from one URL to an another? The answer is sort of. A 301 redirect will do this for you not problem, but will a canonical link?
It was stated to me long ago that a client has a yahoo merchant account that did not allow 301 redirects, and the only thing that could be use was a canonical tag and it worked as I was told it passed over everything amazingly.
Keep in mind though, and this comes back to my answer of sort of, this was a long time ago and things have changed since then. In search engines, everything is a moving target and it's up to use to always do our research before doing our implementation. So with that in mind page rank can be in theory transfered and so can link juice.
Currently Google, Yahoo, Bing, and Ask all support the open Canonical Link Tag, many more search engines are to follow this need.
Google Matt Cutts Discusses Canonical Links