A citation gives credit to the original author(s) of a work. Citations also allow people who are reading your work to be able to find the original sources of information.
Basic citations for a book, for example, include the name(s) of author(s) or editor(s), the title of the book, the publisher's name, the place of publication, and the most recent copyright year.
There are a number of styles that can be used to construct citations. Each style specifies the information to be included in the citation, the order of the information,the format, and the punctuation.
Your instructor may require a particular style. If there is not an assigned style, then choose a style and be consistent with that style throughout your work.
A bibliographic citation, the convention normally used to acknowledge a work quoted in a paper, contains basic information needed to locate an item. There are different formats for citing books, journal articles, chapters in books, dissertations, pamphlets, and other formats.
In general, the publication information, including place of publication, publisher and year, identifies a book. Here is a screenshot of a book citation.
In general, the publication information, including volume number, date and page numbers, identifies a journal article. Here is a screenshot of a journal article citation.
Chapters of books can be identified by the presence of two titles, the title of the chapter and the title of the book. Two names may be listed as well -- the author of the chapter and the editor. The same publication information that appears in a book citation will also appear here; place of publication,publisher, and year. Here is a screenshot of a book chapter citation.
The following are good web resources to help you learn citation formatting and to view citation examples.
Tools that help you keep track of book and article citations and can (using a plugin for MS Word) insert those citations into your paper in the appropriate format save your lots of time and facilitate sharing your explorations with others.
The library has created a detailed guide on how to choose and how to use each of these tools.