What are Canonical tags?

canonical tags mention in Google webmaster tool are same or different where we decide our site to be crawled by www version or non www version

 

When we talk about canonical issues, what we mean is does your site properly handle www versus non-www URLs. As a quick test, type http://yoursite.com into the browser. Be sure to leave off the www. Does the URL redirect to the www version? If not, you are susceptible to a canonical issue. (Unless you choose to display your site without the www, in which case, the site should redirect the www to the non-www version)

 

I make sure all links go to the www version of my domain by updating the htaccess file with:

RewriteEngine On
RewriteCond %{HTTP_HOST} !^www\.yourdomainname\.co.uk$
RewriteRule (.*) http://www.yourdomainname.co.uk/$1 [R=301,L]

 

It is used to avoid duplicate content

 

Thanks for sharing this information, it help for me.

 

Yes this tag is used for overcoming the duplicate webpages.

 

Just avoid the duplicates keyword ranking ,like a signal keyword show in two pages in our websites means, using Canonical URL tags , avoid the issues.

 

Canonical Tag Code used by search engine crawlers/spiders to tell search engines what URL is the original version of your webpage.