The same latte recipe, twice

This page is identical, byte for byte, to another URL on this site.

Two URLs, one page

Duplicate content is the same text living at more than one address: a trailing-slash variant, an http and an https copy, a print version, or, as here, the same article pasted at two paths. A search engine does not want to show the same thing twice, so it picks one URL to keep and drops the rest, and the ranking signals get split across copies that now compete with each other.

How to fix it

Pick one URL to be the real one and point the duplicates at it with a rel=canonical tag, or send a 301 redirect so people and crawlers both land on the single page. On templated sites, watch for URL parameters and slashes creating identical pages you did not mean to make, each one taking a little strength from the page that should rank.