The term Canonical URL refers to a webmaster’s selection of the preferred version of a set of pages with highly similar or duplicate content. For instance, if your website has two URLs, such as https://non.agency/shoes/red and https://non.agency/shop/red-shoes, which display the same content, you can guide search engines to feature your chosen URL in the search results by designating it as the canonical URL. This is accomplished by adding a special HTML element to the head section of the non-preferred page, like so: <link rel="canonical" href="https://non.agency/shoes/red" />. This practice helps to prevent issues related to duplicate content and improves SEO by consolidating ranking signals to a single, authoritative source.
Moreover, a canonical URL serves as a signal to search engines to recognize a specific URL as the “master” or authoritative version among multiple pages that might otherwise be seen as identical. This is particularly useful for managing internal link structures that may be complex or inconsistent. By marking a URL as canonical, you effectively consolidate your SEO efforts and ensure that search engines understand which version of the content is the one you deem most important and relevant to users.