Types of Plagiarism: What You Need to Know

Giving Appropriate Credit

Plagiarism is taking credit for another person's work. You are plagiarizing any time you use text, images, original ideas, or any other


unique, creative material without giving credit to the person who created it. Copying sentences, paragraphs, or whole papers word-for-word, whether from a book, magazine, or website, is plagiarism, except in certain circumstances (see part 2, "Tips to Avoid Plagiarism"). But there are additional types of plagiarism that you may not even be aware of.

Plagiarism Types

When most people think of plagiarism, they think of word-for-word plagiarism, also called copy/paste plagiarism. This form of plagiarism is extremely easy to commit by copying and pasting text from websites, but it also includes typing in text word-for-word from a printed source such as a book.

Word switch plagiarism: Text is copied word-for-word, then certain key words are switched around to disguise the plagiarism.

Sentence rearrangement plagiarism: In complex sentences, there are multiple ways to arrange the clauses. Sentence rearrangement plagiarism is switching the order of clauses in a sentence or paragraph in an attempt to hide the plagiarism.


Original sentence: "Aside from a periodic booster shot a few times during one’s life, vaccinations against diseases like tetanus and measles never need to be repeated." (from "Why Your Flu Shot is Only Good for a Year" by Robyn Broyles)

Word switch plagiarism example: "Except for booster shots a few times during your life, vaccinations against most illnesses never need to be repeated."

Sentence rearrangement plagiarism example: "Vaccinations against diseases like tetanus and measles never need to be repeated, aside from periodic booster shots."

More Complex Examples

You can also commit plagiarism simply by using another person's original ideas without using their exact words. There are several ways in which ideas can be plagiarized.

In metaphor plagiarism, a writer takes a unique, creative metaphor by the original author without giving credit. The original words may not be copied, but the comparison (metaphor) is reused.


Original sentence: "An invasive species in an ecosystem is like a germ in your body: it causes problems with the whole system as it tries to take over."

Metaphor plagiarism example: "You could say an invasive species is like an ecosystem virus, because both try to take over a biological system."

Organizational plagiarism: This type of plagiarism involves copying another person's outline for a whole paper.

Style plagiarism: Similar to organizational plagiarism, style plagiarism copies another author's path of reasoning or explanation. The words may be different, but the way the topic is explained and the order in which ideas are listed are the same.

Idea plagiarism: Authors often write about original ideas they have had or original discoveries they have made. If you repeat one of these original ideas without revealing that another person is the source, you commit idea plagiarism. For example, imagine that a doctor wrote a letter to a medical journal saying that a certain name for a disease is easier for patients to understand than a different, alternative name for that disease. If a person read this letter and then wrote a paper sharing that same idea, but did not give credit to the original authors of the letter, then that person would have committed idea plagiarism. (See note 1.)

Tips to Avoid Plagiarism

I used to think that plagiarism was always intentional, but when I first began editing other people's work, I realized it can happen by accident as well. A student may not know how to give credit properly when he uses another person's words or ideas. Sometimes writers even accidentally incorporate another person's text into their paper without realizing it. Follow these tips to avoid plagiarizing the work of others:

  • Don't look at your source while you are writing. Instead, get the information you need from your source, then put it aside. This practice forces you to use your own words.
  • Other than direct quotes, never, ever copy and paste text directly from a website into your own document. It can accidentally find its way into your own text.
  • If you use a direct quote, always use quotation marks and then indicate the source. The citation usually takes the form of either an endnote or a short note in parentheses. The complete citation is found at the end of the paper in a section with a title like "Works Cited" or "References." Check with your instructor to find out what citation style to use.
  • If you want to use a section of text from your source that is more than about six words long, you normally must use quotation marks and a citation.


An exception to the citation rule for idea is "common knowledge." Repeating "common knowledge" without giving a source is not plagiarism. For example, it can be considered common knowledge that the United States is a country located in North America. This is not an original idea, so repeating it is not idea plagiarism.

An exception to the six-word quotation rule is "common phrases." Sometimes there is only one way to write a sentence or phrase. So-called "common phrases" are exceptions to plagiarism guidelines. They are not really original to begin with, so they do not need to be cited. This situation is most common with technical subjects. For example, in an article about a medication, the phrase "the side effects include nausea and vomiting" cannot easily be reworded. The source of the information should be cited, but the exact words of a short phrase do not need to be placed into quotations. Long passages, however, should always be placed into quotations and cited, even if they seem to consist only of "common words and phrases."

What do you do if you are not sure whether the words in your paper falls under one of these exceptions? If you are in doubt, always assume they are original and follow the rules to avoid plagiarism. It's better to err on the side of caution.


  1. Many of the definitions in this article are based on examples in "Plagiarism: A Student's Guide to Recognizing It and Avoiding It" by Cecilia Barnbaum, Ph.D. I recommend this for further reading.
  2. I created this example situation based on a real letter to a medical journal:

"Morgellons disease: A rapport-enhancing term for delusions of parasitosis." Jenny E. Murase, Jashin J. Wu, John Koo. Journal of the American Academy of Dermatology November 2006 (Vol. 55, Issue 5, pp. 913-914)