Turnitin
（重定向自Turnitin.com）
Turnitin is an Internet-based plagiarism-prevention service created by iParadigms, LLC, first launched in 1997. Typically, universities and high schools buy licenses to submit essays to the Turnitin website, which checks the documents for unoriginal content. The results can be used to identify similarities to existing sources or can be used in formative assessment to help students learn how to avoid plagiarism and improve their writing.