Indexation
Canonical tag
An HTML hint that tells search engines the preferred URL for a piece of content.
Definition
A <link rel="canonical" href="..."> tag in the document head signals which URL Google should treat as the source of truth for duplicate or near-duplicate pages. Misuse — pointing all canonicals to the homepage, drifting between client and server renders, or chaining canonicals — causes indexation loss.
See also
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