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Canonical – Canonical URL

What is a canonical URL?

canonical url

As a website grows in size, it can be difficult to keep pages from becoming duplicates or near-duplicates of each other. This may result in duplicate content difficulties. If you have two comparable sites that are both qualified to rank for the same key term, the search engine simply does not know which of the two URLs to direct visitors to. To resolve this, you can choose a preferred URL, also known as the canonical URL.

The canonical URL is the address of a page defined as being the original and signaled to search engines so that they do not index other pages which reproduced the content of the original.
It is what is called everywhere on the Web meta canonical, canonical tag, rel canonical or even canonical tag.
It is a tag inserted into the HTML code that will tell search engines that the page is canonical.

Canonical URL is the address of a page that search engines are asked to consider original

meta tag

The same page, but different URLs
A canonical URL is a technological solution to the problem of duplicate content. For example, you may have a post or product that is associated with two categories and exists under two URLs. If these URLs are both for the same product, selecting one as the canonical URL instructs Google and other search engines which one to display in search results.
You may also use canonicals to direct search engines to the original version of an article. Assume you've produced a blog article for another party and it's been published on their website. If you want to post it on your site as well, you might agree to do so with a canonical link to the original version.
There is an almost pervasive problem on the Internet when it comes to editorial content.
A text, even a page is quickly copied and republished as is or barely transformed in other websites either for advertising or by plagiarism.
This phenomenon is all the more extensive as the information concerned is interesting. However, the search engine algorithm does not like duplicate content and penalizes it by prohibiting them from accessing SERPs (search results pages). The concern then is that the original page runs the risk of being taken by robots like Google bot for one of the duplicated pages. To overcome this problem, the Google engine offers the solution to the webmaster, which is to indicate the original page as canonical as soon as it is created.
The webmaster will indicate to Google the address in the format <link rel = “canonical” href = “”> and between the tags <head> and </head>.
This will allow him to recognize similar pages created after the original as non-original and to consider only the holder during his page indexing operation.
This selection is doubly beneficial: it does justice to the original content and avoids an overload of indexed pages in the search engine database.

Canonical URL is used to protect against content theft and is not the 301 redirect

canonical url

Obviously, the ideal would be to canonize all the pages of your site.
On the one hand, this is necessary when you have to create internal duplicated pages, that is to say to duplicate a page n times as in the case of a product sheet for example, in order not to have indexed by Google as the most valuable in terms of SEO.
This is also useful when the text on this page is likely to be used by other editors for the creation of their content and especially because some robots are assigned to automatically steal content in order to feed other sites.
This will be the canonical page that the engine will display in the search results pages for a given query.
It should be noted that this solution has a lot of similarity with the 301 redirection which causes the engine to choose one page rather than another.
The difference is that the
canonical URL is for search engines only and that is for indexing while the 301 redirect returns engines and users from an old page to a new one quite simply, which is more like an update.
The usefulness of making this distinction lies in the relevance of the choice of technique to reorient users or engines.
A canonical URL refers to an HTML link element, with the attribute of rel="canonical" (also known as a canonical tag), found in the <head> element of your client’s webpage. It specifies to search engines their preferred URL. That means the canonical URL element informs Google and other search engines to crawl a website, and what URL to index that specific page’s content under. This is important because URLs can have variations, based on a variety of factors, but be serving up the same or similar content. The specification went live in April of 2012, and was described