Duplicate content

Duplicate content is when identical or very similar text appears at different addresses. Google does not want to show users several of the same results, so it picks one and skips the rest. The problem is that it will not always pick the one you care about.

There are two kinds. Internal duplication is repetition within your own site: the same product descriptions across several categories, versions with URL parameters, a page reachable both with and without www. External duplication is when your content is copied onto other sites - or, worse, when you have copied someone else's.

Contrary to the popular myth, this is rarely about a "duplicate penalty". More often the problem is diluted signals: links and SEO power split between the copies instead of strengthening one strong page. The solution is unique content, canonical tags, and tidy addresses. Check the scale of duplication - yours and others' - in the /antyplagiat tool.