Canonical URL

The rel=canonical tag consolidates ranking signals onto one preferred URL when the same content is reachable through multiple addresses — think tracking parameters, print versions, or http vs https. A classic mistake is pointing every page's canonical at the homepage, which tells Google to drop the rest of your site from the index. Canonicals are a hint, not a directive, so keep them consistent with your sitemap and internal links or Google may pick a different URL than you intended.