While plagiarism is usually just the result of careless mistakes, it is still a serious offense. You should be vigilant in every stage of your research and writing to make sure that you get credit for your original ideas and that you give proper credit to those whose work you used to support your argument.
#1- You purposefully place your name on someone else's paper or project. Or, you cut and paste chunks of text from the web and use it as if its your own words.
This is the most blatant form of plagiarism. It's pretty easy to understand how using someone else's entire work (with or without their knowledge) is a bad idea. This includes copy and pasting paragraphs or whole sections from online articles or even websites. The purpose behind most assignments is for the instructor to see your original work, and passing off someone else's hard work as your own is cheating.
#2- You use an author's exact words to explain or describe a concept but don't use quotation marks to cite the source.
Sometimes there's no way you can say something better than what another author has done. In these cases, it's okay to use their exact phrasing, but you need to be sure to indicate that it comes directly from another source (quotation marks) and the source from which it comes (a citation or reference). It's your job to give credit to these other authors. Also, you may want to be aware of how much material you are drawing from other sources. The instructor wants to read your original work, so make sure that there is more of that than information from external sources.
#3- You paraphrase an author's idea or concept using your own words but do not properly credit the idea's original source.
Even if you don't take the information word for word, you still need to credit and cite the original source of these ideas. Since they are your own words you don't need the quotation marks, but you still need the citation or reference at the end of the section to indicate that the idea did not originally come from you.
If you are caught plagiarizing, there can be some serious consequences. At the class level, most instructors address the penalties for plagiarism and cheating in their syllabi. In addition, the College prohibits plagiarism and other forms of cheating in its Honor Code. The Honor Council, which upholds the Honor Code, enforces instances of plagiarism. See the Eagle Handbook for more information about the Honor Code and Honor Council.
The Honor Code categorizes plagiarism as cheating and defines it "...as the use of another person's ideas or thoughts, which are not common knowledge, without acknowledging the source." (Eagle Student Handbook 2015-2016, page 152). See the full text of the Handbook (2019–2020 edition) for more information on the Honor Code and Honor Council.
BC also has additional information about its plagiarism policy on the Writing Center website. You can also see the entire plagiarism policy here:
Here's an excellent video tutorial from the University of Bergen, Norway. It's in Norwegian, so don't forget to enable the English subtitles.