Quoting is when you use someone's exact words in your research.
You might use a direct quote when you feel the author's words express the point better than you could with a summary or paraphrase. For example, if you were writing a paper on film adaptations of Harry Potter and wanted to use a direct quote from a film review, it might look like this:
According to Manolha Dargis' New York Times film review, the Harry Potter series, "has begun to show signs of stress around the edges" (Dargis).