Information gathered from any source - books, journals, films, web sites, even personal conversations and unpublished manuscripts - cannot be reused without citing the source of your information.
"To be fair and ethical, you must acknowledge your debt to the writers of these sources. Failure to do so is a form of ACADEMIC DISHONESTY know as plagiarism." Hacker and Sommers, 502.
Use footnotes or endnotes to give credit to a direct quotation.
Include a bibliography or list of works cited.
Follow guidelines from your instructor about citing your sources correctly. Choose one of the following standard citation formats:
APA - American Psychological Association (used in social sciences and some sciences)
CMS - Chicago Manual of Style (also called University of Chicago/Turabian) (used in other disciplines including humanities)
MLA - Modern Language Association (used in English and humanities)
Hacker, Diane and Nancy Somers. A Writer's Reference, 7th ed. Boston: Bedford St. Martin's, 2011.