One of the main ideas of research is to study what others have published and form your own opinions. When you quote people -- or even when you summarize or paraphrase information found in books, articles or web pages -- you must acknowledge the original author.
If you use someone else's words or ideas without crediting them, you are committing a type of theft called plagiarism. Plagiarism can be as obvious as turning in another person's paper or project as your own, or as sly as simply paraphrasing sections of various works. It is also incorrect to copy text from Web pages or other sources and paste it into your paper without identifying the original author.
How can you avoid plagiarism?