Canonicalization - Centre d'aide pour les webmasters
This article describes how you can use canonical URLs to improve link and ranking signals for content available through multiple URL structures or via syndication. In the world of content management and online shopping systems, it's common for the same content to be accessed through multiple URLs. With content syndication, it's also easy for content to be distributed to different URLs and domains entirely. For example: While these systems make it more convenient to develop and distribute content, they cause some challenges when people use search engines to reach your page. For instance: Consolidating link signals for the duplicate or similar content. To address these issues, we recommend you define a canonical URL for content (or equivalent content) available through multiple URLs. While we encourage you to use any of these methods, none of them are required. Don't use the robots.txt file for canonicalization purposes. Set your preferred domain Read Set your preferred domain for details.
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