Duplicate Content
Duplicate content refers to identical or near-identical content reachable under more than one URL — through parameters, print versions, language variants or copied third-party text — which spreads ranking signals across several pages.
In practice
Technical duplicate content can usually be resolved with canonical tags, consistent internal linking or redirects. Content copied from other websites with no added value of its own falls under Google's spam policies on scraping and should be replaced with original, clearly structured text.