Plagiarism and unauthorized collaboration are very closely related areas of academic dishonesty.
In simplest terms, plagiarism and unauthorized collaboration both involve the same fundamental deception: the representation of another's work as one's own.

Because of this connection, group efforts that extend beyond the limits approved by the instructor often constitute collaboration. For example, an instructor may allow students to work together while researching, but require each student to write a separate report; if the students collaborate while writing the report, they are guilty of both unauthorized collaboration. In this example, each student submits a written work misrepresented as their own, which in fact they have borrowed from other, unattributed sources: the other students.

Remember, plagiarism includes not just copying from a published source, but also submitting work obtained from any source as one's own. If you have any questions, ask your instructor for guidelines regarding collaboration.