What Is a Canonical URL?
A canonical URL is an HTML element that prevents duplicate content. This helps prevent SEO issues by indicating whether a URL is a "canonical" or "preferred" version of a page. If Google discovers multiple pages on the same site that seem to be the same, it will chose the one that is the most complete and useful and marks it as canonical. According to Google, the canonical page will be crawled most regularly; duplicates are crawled less frequently in order to reduce the crawling load on your site.
One of the main reasons why you should choose using a canonical URL is to specify which URL that you want people to see in search results. In other words, if you have a web page accessible by multiple URLs, or different pages with similar content (e.g. separate mobile and desktop versions), you should specify to a search engine which URL is authoritative by designating it as a canonical URL.
If you host content that isn't yours, like partnership posts or affiliate marketing pages, you can still point to the original source of the content in the canonical URL. You do this by making sure all of the URLs contain rel=canonical that points back to the site or page you would like it to direct to. This is a great way to allow republishing permissions without losing any of the SEO value. Read more about this here.
On RebelMouse, you can easily change the "rel=canonical" of a post by putting your desired URL in the Advanced Settings tab of our Entry Editor:
From there, insert a URL in the Source URL field to set your article's canonical URL. You can even choose if your post links out directly to it, or just references it in the source code.
Here's a video of how it works:
If you have questions about this feature, please contact your account manager.