Copyscape
Copyscape is an online tool that website publishers use to detect whether text content may have been plagiarized and reprinted on another web page somewhere on the Internet without the permission of the original content owner.
Content theft is a big problem on the Internet as website publishers often copy content from a website and use it on their website without permission. In a website sale, the seller must disclose whether he legally owns the rights to the content offered for sale as part of the website’s assets. A website buyer can use Copyscape to verify this content ownership.
Content that has not been plagiarized and is unique to a website is often referred to as unique content.