Depends! To start, what citation style is used is generally dependent on what is the standard and preferred style for a field. However, this is not the only factor; when learning, an instructor may have their own personal preferences for citation style. So, with that in mind, it is always important to check with an instructor what citation style they would like you to be using.
To learn more about when to use which style, check out these resources: Citation Style by Discipline from Florida State University Libraries and "Citing Sources: Which citation style should I use?" from the University Libraries of the University of Washington.
In-text citations have two main formats, called parenthetical citations and narrative citations. Parenthetical citations follow a piece of information with the information contained in a set of parentheses. Narrative citations introduce information about the citation in the body of the sentence with the information (i.e. in the narrative), though they likely still contain a part or two in parentheses, as it can be difficult to include all of the information in the narrative.
If I am citing an article whose bibliographic citation is as follows in APA (7th edition):
Kogan, L. R., Little, S., & Oxley, J. (2021). Dog and cat owners’ use of online Facebook groups for pet health information. Health Information & Libraries Journal, 38(3), 203–223. https://doi.org/10.1111/hir.12351
in-text citations for this source could look like any of the following:
APA: the acronym for the citation style developed and maintained by the American Psychological Association.
Bibliographic citation: a citation that is present at the end of a work that contains all the necessary and relevant elements of the citation as dictated by the citation style to guide a reader back to the original source; can be considered a "full" citation.
Chicago: the name for the citation style developed and maintained by the University of Chicago Press. Is also associated with the similar style of Turabian; however, they are different.
Citation: something indicating that information or thought in a piece of literature (generally, but not always, scholarly in nature) is not original to the author of the media in question and was learned from an outside source that enables people to find the original source. Is formally created to align with a style, and is comprised of two parts, though what two parts vary based on the citation style.
Citation style: a defined method of formatting a paper (and through that, citations); styles are established by professional organizations to meet their specific needs and can be associated with or preferred by an academic field; the three main citation styles in the United States education system are APA, MLA, and Chicago.
Endnotes: a format of citations where notes relating to each citation made in-text are gathered at the end of the document in question for review. Are indicated using a superscript number (a small number that follows text and is raised above the text that precedes it; think of the blue numbers on Wikipedia, which uses endnotes).
Footnotes: a format of citations where notes relating to each citation made in-text are gathered at the end of the page where the citation was made for review. Are indicated using a superscript number (a small number that follows text and is raised above the text that precedes it; think of the blue numbers on Wikipedia).
In-text citation: part of a citation that is found in the text of a piece of work that indicates which bibliographic citation to look at to find the source of that information, and where in the original source to find it. Has two types, parenthetical citation and narrative citation. Learn more here.
MLA: the acronym for the citation style developed and maintained by the Modern Language Association.
Narrative citation: a type of in-text citation that is formated to provide the necessary citation information in a sentence while following the flow of a sentence. For example, "as Granite (2022) suggests..."
Parenthetical citation: a type of in-text citation that provides the citation information after information from the source has been provided contained within a set of parentheses. For example "you can return or sell your textbooks to the bookstore at the end of the semester (Pine Technical & Community College, 2022)."
The short answer is that we cite so that academic work is as accurate as possible, for both the present and the future.
The long answer is that when things are created, especially in academics, in order to enable us to accurately assess and evaluate them, they need to properly reflect what went into their creation. This is for several reasons, including for the benefit of future researchers who may want to build on what was published and can use citations to find other resources, people who are curious about the topic in question and want to learn more, for someone who is checking to see that all of the information in a source is accurate, for the people who are being cited to know that their work is being built upon and that there is a discussion on the topic to be had with other researchers, and so that the people who are being cited receive appropriate credit for the work that they have done (improper credit is called plagiarism and is discussed on a different page of this guide). These are all really important factors in enabling fields, topics, and ideas to continue to grow and evolve, and they aren't possible without proper citations. Improperly formatted citations can make things almost impossible to find, putting in-text citations in the wrong spot can result in information being lost, and failing to cite at all is just theft of somebody else's ideas and work. And while the importance of citations generally gets boiled down to that last point, all of these are important factors for why we cite.
You must cite something in anything you create that is not original to you AND it has had an influence on the content of your creation. This includes, BUT IS NOT LIMITED TO, thoughts, facts, statistics, designs, research, movies, music, books, magazines, newspapers, quotes, historical documents, press releases, websites, interviews, speeches, pieces of art, podcasts, social media posts, blogs, YouTube videos, patents, manuals, emails, or interviews.
Basically, if you didn't create it and aren't currently creating it with what you're creating at that moment, and it is informing the work you are doing, cite it.
(The Yale Poorvu Center for Teaching and Learning has a great page that goes into more detail if you are interested)
The general rule of thumb of citation is to cite, even when you are not sure you have to. It is better to over-cite than to under-cite; the former may annoy someone, while the other will result in negative consequences.
There are some generally accepted exceptions to this (and if you want to learn more about them, Boston University's School of Public Health has a great guide addressing this topic), but unless you are absolutely sure something is one of these exceptions, always default to citing.
If you have any questions, please, ask early and ask often!
"How" is a bit of tricky question when it comes to citations, as the answer is both simple and complex. The simple answer is that in order to appropriately cite a source, you must use a citation style (see the box on "What Citation Style Do I Use? if you have questions about that topic). The complex answer is that you must use a citation style, but each citation style is unique, so there's not one way to do it, and the styles (though logical from an organizational perspective) are not intuitive or easy to learn. Most professionals you meet are likely unable to do them freehand and probably use resources for help.
These styles are created so that there is a uniform format for papers in a field for several reasons, including ease of reading and easy access to and finding of sources. Generally, they're fairly distinct from each other, but they may not look that way if you are unfamiliar with them. So, if you have any questions about citing, the most important thing to know is what citation style you are going to be using. That will enable you to best find resources or get guidance on that topic.
In the U.S. there are three primarily used citation styles:
These aren't gone into detail in this guide, but check out the "Find Out More" box if you are looking for resources on them.
"Works Cited," "Bibliography," and "References" are three terms that are often (incorrectly) used interchangeably because they conceptually refer to the same thing, though they are distinct from each other. Each refers to the list of full citations that accompanies your work at the end of your paper, presentation, etc. However, it is important to remember that they are not the same.
"Works Cited" is what the list is called in MLA citations.
"References" is what the list is called in APA citations.
"Bibliography" is the general term for the list in question, but is not used in any of the three main citation styles, though it is used in some other ones.
You may be wondering what Chicago style uses, since it doesn't use any of these three. Chicago uses footnotes or endnotes, which are defined in "Citing Sources Vocabulary" above.
Speaking anecdotally, this is the experience of a lot of people, so first, know that you're not alone in having this question.
Second, know that just because you don't learn a style in a classroom, doesn't mean you're totally out of luck. There are tons of resources out there that will help you navigate learning a new style!
There are a lot of online resources that can support you in learning about other citation styles, but remember that not all of them are accurate. The one that is commonly raised above the rest is the Purdue Online Writing Lab (OWL), which is a great trustworthy resource. You can also trust most resources that are in a .edu domain (meaning that they have .edu at the end of the base URL, before any slashes (/); something that has .edu in the beginning or the middle is probably a scam!), since that means the source is from an authorized educational institution.
You can also use the official citation handbooks published by the citation style authorities. Citation styles are updated occasionally to update the style for new information sources, change guidelines, or make new considerations with the changing information environment. Our library has both the MLA and APA handbooks available for student use.
If you'd rather be walked through citation or are still wanting more help, you can always schedule an appointment with someone to have them help you with your citations. We recommend scheduling with Sara Carman, the PTCC librarian, as she can also help with any other general research questions you may have. Schedule an appointment with her here.
A supplementary resource to all of these are citation managers and/or citation generators. Managers such as Zotero or EndNote have been increasing in popularity over the past several years, and can be a great way to lighten the load of creating and organizing citations, as they can create citations by having you input information or a link. However, they are NOT to be used without oversight and checking for accuracy. They are not 100% correct and will generate errors if you are not monitoring them closely.