Plagiarism is using another person's words or ideas without giving them credit. No matter where the text comes from, and even if you paraphrase (put the other writer's idea into your own words), you must give always give credit to the original source.
A student must give credit to the originality of others and acknowledge an indebtedness whenever:
1. Directly quoting
2. Using another person's ideas, opinions, or theories;
3. Paraphrasing the words, ideas, opinions, or theories of others, whether oral or written;
4. Borrowing facts, statistics, or illustrative material; or
5. Offering materials assembled or collected by others without acknowledgment.
Plagiarism is easily avoided by correct citation. To review the proper way to quote, paraphrase and cite research sources, try the library's Plagiarism Tutorial.
(Mtmelendez. Tourist Section of the Willemstad Harbor in Curacao. 2005. Photograph. Willemstad. Wikimedia Commons. Spring 2005. Web. 24 Sept. 2013.
For more citation information, you can use these online resources.