A rel=canonical link element naming the preferred URL among duplicates, so ranking signals consolidate onto one address instead of splitting across copies.
Canonical Tag is a rel="canonical" link element in a page's head that names the preferred URL among duplicate or near-duplicate versions of the same content. It tells a search engine which URL to treat as the master, so ranking signals from every copy consolidate onto one address instead of being split across several.
It solves the everyday problem of one piece of content living at many URLs: tracking parameters, print versions, HTTP and HTTPS, trailing slashes, or the same page served under two hostnames. Without a clear canonical, an engine picks one itself, which may not be the version you want indexed and shown.
The same consolidation matters for AI. Systems retrieve and cite from the indexed web, so duplicate URLs dilute the authority and signals that decide which version gets grounded into an answer. Pointing every duplicate at one canonical concentrates that weight on a single, correct URL, which is part of clean, retrievable AI visibility.
