1. Claiming someone else's work (words and/or ideas) as your own.
2. An academic offense that can result in a lowered or even a failing grade, suspension, or--in severe cases--dismissal from the University.
3. Not a breach of law, but a profound breach of ethics.
4. Just plain DUMB, because properly acknowledging the sources undergirding your own work only improves your grade. There is no downside to doing the right thing, whereas the penalties for plagiarism can be severe and long-term.
Understand plagiarism and avoid it: