Respondus LockDown Browser is a browser that locks students into the quiz environment during a quiz. Students can't access other software during a quiz with LockDown Browser. Instructors can also choose to apply Respondus Monitor which records students taking quizzes via webcam.
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We have a student guide on LockDown Browser: http://departments.bloomu.edu/imdc/Docs/Respondus/LDB/student/respondusLDB_student_guide.pdf