plagiarism=bad.

When I read a book or article, I expect what I am reading to be the true work of the author, unless otherwise stated. I believe most people do this--it's natural. It's what writers do out of respect for the work of others. If something is not theirs, then they should give credit where it's due, or not use it at all. Students might not take this as seriously as employed writers because of a possible lack of seriousness regarding a care for the subject on which they are writing or a lack of time or just plain disregard for doing what is expected of them.
Writing is a serious method of transferring the human mind to paper. It is a visible manifestation of the works of the human mind all over the world. When someone puts their thoughts to paper, it is something that no one else can take credit for. Of course these thoughts can be used when the credit is given where it is due, but there is no excuse for taking them without permission and claiming them as one's own. Research is a scary area to deal in when worrying about plagiarism. If one little thing is not cited, a person can get into loads of trouble. Plagiarism is outright stealing--a plagiarist is a thief. They may not be stealing a tv or car, but for many people, thoughts are worth much more than anything material.
As human beings have attempted to create their own ideas and bring changes to the world, there are now loads of information, available at our fingertips for our own progression and learning. These works have usually been written in efforts to bring change and diversity to the world. With so much information, it is easy to simply write something down and take credit for it; there's so much information that almost nothing is completely original anymore. But this is dishonest--it is unacceptable to do this. It happens every day, but it goes against any respect for the ideas of others. As we are writers, it is our responsibility to provide truth to readers. It is our duty to be respectful and honest.