Unicheck is a similarity-detection service that is integrated into Doane's instance of Canvas. You can activate Unicheck on Assignments in Canvas. It is not currently available for Discussions or Quizzes.
The video below provides direction for basic assignment configuration using Unicheck. You can find more detailed information and support on the Unicheck website.
It's always best to turn on Unicheck before students start submitting to an assignment, but you can still activate Unicheck after students have submitted; however, there are few additional considerations. View the instructions for Turning on Unicheck after Students Make Submissions (Doane login required).