While cheating on exams or plagiarism of papers may have been common in high school, the University is quite strict in dealing with these issues.

Incidents of academic dishonesty are referred to Dean Nurse's Office.  You can refer to the rules here.

One of the best sites on campus for academic integrity resources is the UM library site including a self test to see if you understand the basic issues.

The English Department has a very clear statement on their web site explaining plagiarism. 

Whenever you are in doubt, ask your professor!!