For college students the main purpose of citation is so that your instructor can find the sources you used. Your instructor may want to evaluate the sources you used to see if they are college level and appropriate for your assignment.
For authors publishing in their field the same is true. Readers need to be able to check the sources used. It is also important to credit sources used; if not, the author is taking credit for someone else's research and that is plagiarism.
zoterbib can help you build your citations in multiple styles, including APA, MLA, Chicago/Turabian, ACS, GSA and more. It can be especially helpful when you are citing something unusual like an image, television or federal statute. Want more? Try How to Use Zoterobib.
There are several styles of citation and even though they may require the same basic information, different fields of study use different styles. Your instructor will let you know which citation style they want you to use. The APA and MLA guides Grab a Citation page that shows you step by step how you can easily grab a citation for your sources from our databases.