You should understand the distinction between source materials that require acknowledgment and those that do not. Now that huge amounts of reliable information are available online, conventions regarding acknowledgment, fair use, and source citation are shifting. It is still important, however, to be as careful as possible in providing citations so that your readers will know where you got your information.
Materials that do not require acknowledgment
Common knowledge. If most readers know a fact, you probably do not need to cite a source for it. You do not need to credit a source to say that Barack Obama was reelected president in 2012, for example.
Facts available in a wide variety of sources. If a number of encyclopedias, almanacs, reputable Web sites, or textbooks include a certain piece of information, you usually need not cite a specific source for it. For instance, you would not need to cite a source if you write that the Japanese bombed Pearl Harbor on December 7, 1941.
Findings from field research. If you conduct observations or surveys, announce your findings as your own. Acknowledge people you interview as individuals rather than as part of a survey.
If you are not sure whether a fact, an observation, or a piece of information requires acknowledgment, err on the side of safety, and cite the source.
Materials that require acknowledgment
For material that does not fall under the preceding categories, credit sources as fully as possible. Follow the conventions of the citation style you are using (see Chapters 32–35), and include each source in a bibliography or list of works cited.
Quotations, paraphrases, and summaries. Whenever you use another person’s words, ideas, or opinions, credit the source. Even though the wording of a paraphrase or summary is your own, you should still acknowledge the source (12g and 13b–d).
Facts that aren’t widely known or claims that are arguable. If your readers would be unlikely to know a fact, or if an author presents as fact a claim that may or may not be true, cite the source. To claim, for instance, that Switzerland is amassing an offensive nuclear arsenal would demand a source citation because Switzerland has long been an officially neutral state. If you are not sure whether a fact will be familiar to your readers or whether a statement is arguable, go ahead and cite the source.
Images, statistics, charts, tables, graphs, and other visuals from any source. Credit all visual and statistical material not derived from your own field research, even if you create your own graph or table from the data provided in a source.
Help provided by others. If an instructor gave you a good idea or if friends responded to your draft or helped you conduct surveys, give credit—usually in a footnote that says something like “Thanks to Kiah Williams, who first suggested this connection.”
Here is a quick-reference chart to guide you in deciding whether or not you need to acknowledge a source:
NEED TO ACKNOWLEDGE
DON’T NEED TO ACKNOWLEDGE
quotations
paraphrases or summaries of a source
ideas you glean from a source
little-known or disputed facts
graphs, tables, and other statistical information from a source
photographs, visuals, video, or sound taken from sources
experiments conducted by others
interviews that are not part of a survey
organization or structure taken from a source
help or advice from an instructor or another student
your own ideas expressed in your own words
your own observations, surveys, and findings from field research you conduct yourself
common knowledge—facts known to most readers
drawings and other visuals, audio recordings, video, and any other materials you create on your own
facts available in many reliable sources, whether or not they are common knowledge