There is a variety of different citation styles, and it can be confusing. Different disciplines usually use different styles: MLA style is typically used by the Humanities, APA style is often used by Education and Psychology. If you're not sure what style you should use, ask your teacher!
How to Recognize Plagiarism: Tutorials and Tests
Resources and information about plagiarism
Purdue University's Online Writing Lab (OWL)
Includes resources and instructional materials to assist with a variety of writing projects.
You do need to cite anything that you quote directly from another source, whether that's a movie, an audio clip, a newspaper, or a scholarly article. You should also cite information that you learned from another source. If you're paraphrasing or summarizing someone else's information, you still need to give them credit for coming up with the idea.
You don't need to cite things that are considered "common knowledge", meaning basic facts or other things most people know. For example: you wouldn't need to cite the fact that the capital of France is Paris. You also don't need to cite your own experiences, thoughts, or conclusions about a subject.
When in doubt - cite it!
Databases and websites will often have tools to help you format your citations. These can be helpful in getting started with your citations, but no tool is perfect - you will need to double-check each citation, no matter what you use to generate it! Citation tools tend to make mistakes with personal names, capitalization and punctuation most frequently, so pay close attention to that in particular. The YIS databases will generate citations and even export them to Zotero where you can keep all your citations together. Zotero will also make a works cited/references page for you.
Consult the posters in the MLA and APA tabs for more information on in-text citations (parenthetical citations).
There are lots of reasons to cite your work. It helps you avoid plagiarizing. It allows the reader to find your research sources. Think of citations as footprints leading the reader through some of the steps you took to reach your conclusions. It provides evidence for your arguments and adds credibility to your work by demonstrating that you have sought out and considered a variety of viewpoints on a given topic. And finally, it's standard practice for scholars and students engaged in written academic conversations. By citing your sources, you demonstrate that you are responding to this person, agreeing with that person, adding something to what so-and-so said and so forth.