About 60% of the internet is duplicate, according to Google. At the Google Search Central Live event that took place the other day in Singapore, Gary Illyes, Google Webmaster Trends Analyst, shared this slide.
Duplicate content refers to identical content that is found on several pages in Google search results, in the same website or on other websites.
In other words, and according to Google:
“Duplicate content generally refers to substantive blocks of content within or across domains that either completely match other content or are appreciably similar. Mostly, this is not deceptive in origin.”
Therefore, it is important to avoid this type of content in favor of unique content for successful search engine optimization (SEO).