Zotero is a computer program that provides a storage space for citations (references to works you use in your writing) and formats them in any of hundreds of citation formats as you write your paper, article, annotated bibliography, dissertation or book. Follow the link below for instructions on how to download and use it.
The MU Libraries has a guide on citation styles and tools. Use the links below to go directly to information on APA, Chicago, and MLA styles or click on "Citation Styles: The Basics" to get an overview. Don't forget about the Writing Center on campus when you have a style question you can't answer. They have tutors online as well as in-person including in Ellis Library (directly above the coffee shop).