Turnitin is an online tool that assists educators in detecting plagiarism in student papers. It scans submitted papers against a proprietary database (billions of current and archived web pages, a repository of works other students have submitted to Turnitin in the past, and a collection of documents, which comprises thousands of periodicals, journals, and publications). 

Turnitin service can be accessed by students or instructors independently. Alternatively, Turnitin can be integrated in learning management systems (LMSs), with opt-in or opt-out options for its use in courses.