Overview: What is Plagiarism?
Plagiarism is the unauthorized or unacknowledged use of another person's academic or scholarly work. Done on purpose, it is cheating. Done accidentally, it is no less serious. Regardless of how it occurs, plagiarism is a theft of intellectual property and a violation of an ironclad rule demanding "credit be given where credit is due".
Quite often, carelessness, procrastination and inexperience are contributing factors behind a charge of plagiarism. Developing good research habits and learning how to properly cite and document your sources will keep you above suspicion and protect you from such charges.
If you intend on pursuing an academic career, your scholarship will undergo constant examination by your peers and colleagues. Your reputation will be earned when you earn their respect; how you will be judged will be based, in part, on how you treat the intellectual property of others.
Acknowledging those from whom you have learned assigns credibility to your work and creates a record that other researchers can refer to and build upon. More importantly, your own skill and talent as a scholar will begin to take shape.
As respect for your scholarship grows, so too will your inclusion in the ongoing conversation among experts, past and present, within your specific field of study. Your own body of intellectual property will not be far behind.