Canonical URL
A canonical URL is the preferred version of a page when the same content exists at several addresses, set with a rel="canonical" link element.
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What Canonical URL means
Duplicates happen with tracking parameters, http and https, trailing slashes or syndicated copies. The canonical tag tells search engines which URL to index and credit. Google treats it as a strong hint and may choose differently.
<link rel="canonical" href="https://example.com/page" />