Duplicate content
Also called: double content
Duplicate content is a commonly used term within search engine optimization (SEO). It means that the same content (usually textual content) appears on multiple Web pages.
Duplicate content can be either fully copied text or pages or shorter passages. The duplicate content can appear on different pages within the same domain name. The duplicate content can also be spread across multiple websites.
Avoid duplicate content
If several pages contain more or less identical content, this can have a negative impact on the findability of these pages in search engines such as Google and Bing. Search engines have no interest in presenting users with the same results multiple times. They prefer to link to relevant, quality unique content.
Generally, when duplicate content is detected, search engines will decide which page to point to in search results. However, posting duplicate content can also cause a page or an entire site to incur a penalty. This may even mean that the content is no longer findable at all.
Therefore, a general advice is to avoid duplicate content as much as possible. Do not copy texts from other websites and avoid reusing content on multiple pages within your own website. Also, when posting texts on social media and guest posting to external websites, make use of unique content as much as possible.
Benign and malicious duplicate content
Duplicate content is often created by accident. For example, because a website can be accessed with and without a www in front of the domain name. Or because a mobile website exists with the same texts. Sometimes the pages of a website can be accessed via different URLs (with or without a slash or .html at the end).
Another example is a catalog with underlying pages, such as products or news articles, where the same links and descriptions appear more often. In general, these examples are not immediately harmful, but any adverse effects can be prevented with the right technical measures.
When the same content is published on websites of different owners or publishers, this can also constitute plagiarism. This is often done in an attempt to manipulate search results in order to get traffic from search engines. This is also referred to as search engine spam or spamdexing. At worst, the very original source may be classified as plagiarism.
