Duplicate content is a problem for search engines, and that makes it a problem for SEOs. Google strongly dislikes including the same content more than once in search results, and if content exists in more than one place on a site, search engine algorithms have trouble determining which version they should include or exclude.
They also have difficulty knowing where to assign link juice and authority. This confusion can lead to sites experiencing a loss of traffic and reduced SERP rankings. Therefore, the “rel=canonical” element intends to help search engines. It does this by telling them which page is “the page” for specific content.
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