Academic Integrity:

From UNLV Policies in the Syllabi Content memo:

Academic Misconduct: Academic integrity is a legitimate concern for every member of the University community. We all share in upholding the fundamental values of honesty, trust, respect, fairness, responsibility, and professionalism. By choosing to join the UNLV community, students accept the expectations of the Student Academic Misconduct Policy, and are encouraged to always take the ethical path whenever faced with choices. Students enrolling at UNLV assume the obligation to conduct themselves in a manner compatible with UNLV's educational mission. An example of academic misconduct is plagiarism. Plagiarism is using the words or ideas of another person, from the Internet or any other source without proper citation of the source(s).

See also:

1. Office of Student Conduct.
2. Office of Student Conduct: Forms and Policies.
3. Office of Student Conduct: Student Conduct Code.
4. Student Academic Misconduct Policy
5. Instructor Flow Chart: Student Academic Misconduct incident / Academic Misconduct Report Form.
6. OSC Flow Chart Student Misconduct / Student Conduct Incident Report.

Cheating on exams is absolutely out of line. It's shameful to do it. It is attempting to steal from your fellow students.

Cheating gets a zero on that exam plus maybe other course penalties and the Office of Student Conduct will apply their own penalties.

About assignments: in the instructor's view, teaching a fellow student about a problem line by line is fine. Allowing them to directly copy is NOT.

Another important issue under academic integrity is copyright.

Copyright: The University requires all members of the University Community to familiarize themselves and to follow copyright and fair use requirements. You are individually and solely responsible for violations of copyright and fair use laws. The university will neither protect nor defend you nor assume any responsibility for employee or student violations of fair use laws. Violations of copyright laws could subject you to federal and state civil penalties and criminal liability, as well as disciplinary action under University policies. Additional information can be found at http://provost.unlv.edu/copyright.

Actually, becoming really familiar with copyright law is an enormous task.

It's simply best NOT to use copyrighted material whenever possible.

About all that is absolutely fair use are short quotes of text.