Information is written for different purposes.
Information is written for different audiences.
Information is presented in different formats.
Always consider the type of information you need and what you need it for. Choose information appropriately for your purpose, audience, and preferred format.
Most of the resources collected on this guide are intended to inform or educate (their purpose) and are written for scholarly or professional readers (their audience). Use the navigation on the left to learn more about some different source formats you may encounter in your studies.
We can group information sources into three basic categories: primary, secondary, and tertiary. When we make distinctions between these three categories of sources, we are relating the information itself to the context in which it was created. Noting this relationship between creation and context helps us understand the big picture in which information operates, and prompts us to consider whose voices we are including in our research, and whose voices may be left out.
| Primary Sources | Secondary Sources | Tertiary Sources | |
|---|---|---|---|
| What are they? | First-hand observations or experiences of an event. They can also be the original sources of information before they have been analyzed, such as statistical data sets. | Sources created after an event occurred to offer a review or an analysis of the event; they provide an interpretation of the primary source or data without offering new data. | Compilations of information coming from secondary and primary sources; these can be lists or collections, and are generally reference material that can help you find, or direct you to, secondary and primary sources. |
| Examples |
Eyewitness reports (interviews, photographs) Speeches, diaries, memoirs Empirical research Original documents, historical newspaper articles Literary works (novels, plays, poems), artworks Tweets |
Biographies, nonfiction books Editorials Literary criticism and reviews Periodicals (such as scholarly journals, magazines, or newspapers) Retweets |
Encyclopedias, dictionaries Indexes Databases, catalogs Most textbooks |
Information reformatted from Introduction to College Research: Types of Sources by Walter D. Butler, Aloha Sargent, and Kelsey Smith. CC-BY.
When selecting sources, there are two main questions to ask as you decide whether or not it will meet your needs:
Is this source relevant to my information need?
Is this a trustworthy source?
There are other considerations which can help you answer those (potentially complex) questions, but it's important to keep in mind that your sources should answer your question and be quality sources deserving of your trust.
To evaluate each source:
There are other more detailed strategies you can follow for evaluating sources (some examples include asking the 5 W questions or using a source evaluation checklist), but, unfortunately, there's not always an easy yes or no answer here. Instead you need to make a thoughtful decision using any information you can find about the author, website, publisher, or material. The quality of the answer to your information need depends on this, so don't skip this process when choosing sources!
The sources included on this guide are generally of high quality and good credibility, but it's always important to keep your information filter turned ON.
