The Canonical Tag ( rel=canonical element) often called the “canonical link”. It is an HTML element that helps Search Engines prevent duplicate content issues by specifying the “canonical URL”, the “preferred” version of a web page. Actually we give Canonical tag just for search engines not for users. It also help. in Search engine Optimization of Web pages.
In canonical link we give URL of preferred Web Page or Master page .This tag is present in HTML header portion where meta Title and meta Description tags are present. For Canonical Tag following Syntax is Used:
<link rel=”canonical” href=”http://www.domain.com/your-preferred-url/” />
It tells search engine/Webmasters that one URL is equivalent to another URL (preferred Page URL) where search results are related to this page. The main use of this tag is to avoid issues related to duplicate content on your website which generally occurs due to similar URL parameters or the existence of similar content. The canonical tag was introduced to handle duplicate content for web masters who have similar or identical content within their blog.There are many legitimate reasons for duplicate content, specially system generated URLs. These include:
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