A Canonical tag is a special HTML element that helps webmasters tell search engines which version of a web page is considered the “official” or “original.” This is particularly useful for resolving issues with duplicate content (Duplicate content) to avoid that SEO (search engine optimization) can have a negative impact on a website.
Imagine that you published the same article on two different URLs on your website. Without a canonical tag, search engines could regard both pages as separate content, which could lead to a division of SEO values. By using a canonical tag, you can mark one of the URLs as the preferred version. Search engines then recognize that they should index that version and display it in search results while ignoring the other page.
Setting a canonical tag is easy. You add the tag to <head>-enter the HTML code of the page in question, as follows:
<link rel="canonical" href="http://www.beispiel.de/bevorzugte-url.html" />
Here is href the link to the page that you want to define as the canonical or preferred version. This ensures that search engines know which URL to prioritize, improving the visibility and effectiveness of your SEO efforts.
