To start, your instructor will likely tell you what type of sources they want you to use for each assignment; pay close attention to what they say, because using the wrong type of source can seriously affect your performance on the assignment from the beginning.
If your instructor didn't give you instructions on what type of sources you need, one quick way is to determine what information you will need for the assignment; do you need numbers and data? Do you need a contemporary source or a historical one? Are you looking for a piece written by a professional in the field, or by someone from outside the field? Is it information that was known widely, or just locally? With this information, you can work backward to determine what type of source will work best for you.
Remember, if you have questions, ask early and ask often! Waiting until the last minute may not only feel awkward, it may limit what you're able to access to use, especially if it is a busy time of the semester, such as finals week.
DOI: digital object identifier; a unique identifier that is occasionally assigned to published scholarly articles to provide a permanent link and identifier to the article.
Grey literature: "literature produced by government, academics, business and industry in print and electronic formats, but which is not controlled by commercial publishers" ("Grey Literature - Research Process."); read more from Northcentral University Library here.
Peer-reviewed: a publication that was evaluated by professionals in the field and/or topic it is published in prior to publication; may refer to an individual article, or an item that is comprised of such articles. Can be used synonymously with "scholarly."
Popular: a publication written for a general audience; does not use specialized language or jargon; can be online or in print.
Primary source: a source that is original to or a first-hand account of the event, person, or phenomenon it is about. Examples can include diaries, newspapers, interviews, photographs, and original research.
Open access: a model of electronic publishing that includes making content available without barriers to access, such as paywalls. Articles that are open access can be just as reputable and important as those that are not. Learn more about open access here: creativecommons.org/about/program-areas/open-access/.
Secondary source: a source that was written about an event, person, or phenomenon it is about that is not first-hand, but can be created from first-hand accounts; it also is likely not contemporaneous to the topic. Examples can include books, articles, documentaries, or podcasts.
Scholarly: a publication that is aimed towards professionals in a field; defined by field-specific topics and language; can be online or in-print. Can be used synonymously with "peer-reviewed."
Tertiary source: a source that compiles the information presented by primary and secondary sources into what is generally a more comprehensive source. Examples include dictionaries, encyclopedias, or wikis. Is not always used, and some individuals consider these to be secondary sources.
White papers: a publication that aims to guide its audience in solving a problem; may be governmental in nature or have a marketing focus; read more at "Policy Papers and Policy Analysis".
"Policy Papers and Policy Analysis." Stanford Law School, law.stanford.edu/wp-content/uploads/2015/04/Definitions-of-White-Papers-Briefing-Books-Memos-2.pdf. Accessed 14 Jan. 2022.
"Grey Literature - Research Process." Northcentral University Library, 13 Jan. 2022, ncu.libguides.com/researchprocess/greyliterature. Accessed 14 Jan. 2022.
Below is a list of sources you may come across while you are doing research; this list is not extensive, and if you have any questions about a source you have found and if you can and should use it, please ask!
| Book | Encyclopedia | Newspaper |
| Scholarly Journal | Magazine | Professional/Trade Journal |
| Journal Article | Social Media Post | Website |
| Interview | Podcast | |
| Lecture Notes | Film | TV Show |
| YouTube Video | Presentation | News Report |
"Periodical" is a broad term used for publications that are published on a periodic basis. Included in this category are magazines, professional/trade journals, and scholarly journals, three publications that, though distinct, can often get confused with each other.
Magazines are publications that are geared towards a topical or demographic audience; articles are generally shorter and can cover topics that are deemed relevant to the focus of the magazine, which can be broad. Physical magazines are printed on glossy paper and filled with images. As a popular publication, they are written to be readable by any person. Probably published on a weekly or monthly basis.
Professional/Trade Journals are aimed towards people who work or are interested in working is a specific professional field, profession, or even specific professional positions. They can also be regional. Articles focus on topics specifically for the audience, such as news in the field or professional development. Uses language specific to the field and may not be accessible to some, but could be understood by non-professionals. Generally published more infrequently than a magazine, but frequency varies by publication.
Scholarly Journals are publications focusing on research in a field, specifically publishing new research reports, or discussions about and reviews of research. Articles are generally longer, some reaching dozens of pages. Articles generally don't have images unless they are part of the article, and they are not interrupted by advertisements or other articles. Articles must be submitted and approved for publication. Can cover a wide variety of topics or be very specific. Very field-specific language used frequently; only intended to be read by those who are professionals in the topic. Published less frequently, with the most frequent being once a month and the least frequent being once a year.