When you "acknowledge" a source, you are giving credit to the original author of the material you have used in your assignment. You are noting that an idea, phrase, data, etc., is not an original idea of your own; rather you have learned the material from another author. Other words for the verb "to acknowledge" are "to attribute" or "to credit." In almost all disciplines, writers acknowledge sources in two ways: citations and bibliographic entries.
Creative or original images, language, or ideas that belong to other people, not ourselves. These other people might be writers, scholars, artists, professors, lecturers, or subjects who are interviewed. Your friend or fellow student can, of course, be any of these things, so a student has rights to his or her intellectual property, even if his or her paper is not published.
A "citation" is a written notation that indicates the source of the material you have used in your paper in every instance that you have done so. Different disciplines require different types of citations. Some disciplines require you to use parenthetical references within the paragraphs or your paper (MLA style, APA style) each time you use material from another source. Other disciplines require footnotes or endnotes at the bottom of the page or end of the assignment (Chicago style, Turabian).
Citations are not the same as the complete list of sources--usually called a bibliography or works cited list--required in almost all assignments. Citations in your paper, whether they are parenthetical references, footnotes, or endnotes--do two things:
Also called a list of "Works Cited" or "Sources," this is the page that lists all of the sources that you have relied upon in your assignment. Many documentation styles require both citations (parenthetical references, endnotes or footnotes) and a bibliography. Some styles do not require both. All bibliographies must follow a specific format. The documentation style used in your discipline will tell you what to name this list and how to format it.
Your "sources" are your "research"--the works that you have located, read and relied upon to create your finished assignment. These works may be scholarly articles, reports, government documents, reference books, newspaper reports or articles, web pages, electronic sources, lectures, works of art, interviews, television programs, or other original work by scholars and experts.