You know it's important to evaluate information you find on the open web. It's also a good idea to evaluate other sources--even those from scholarly books and journals--to understand how the information and ideas they express are relevant to your research.
Although you may decide to use any or all of the information you find, you need to evaluate that information so that you understand where the information comes from and how the ideas are relevant to your research.
For example, if you choose to include biased information or out-of-date scientific theories, you must recognize those materials for what they are and indicate in your paper or presentation why that information is important within the context of your research.
The differences between primary and secondary can sometimes be ambiguous, but often a scholarly source is meant when a faculty asks for "a secondary source," while primary is everything else and is tied to particular time (whether a tweet from yesterday, a government document from twenty years ago, a painting, a newspaper article, or an ancient codex of laws. When evaluating sources, it is helpful to ask the questions below.
Questions to ask
Questions to ask as you evaluate the sources you find and the
information and ideas they present:
Who is the author?
What are the author's credentials?
How easy is it to identify who wrote this information?
What is the author's educational background?
What is the author's area of expertise?
Have other scholars cited this author's work?
Did your professor or another expert recommend this author's
What organization sponsors or employs the author?
Why was the source written?
Is the information in it fact, opinion or propaganda?
Does the author want people who read it to take some action? For
instance, are you being persuaded to buy something or to vote for
Is the author's point of view objective and impartial? Can you
detect a bias?
How was it written?
Does the author tell how facts were gathered? Were they gathered
from unbiased sources?
Is there any documentation offered, for instance, do you find a
bibliography or other "credits"?
Why was it posted or published?
Who is hosting this website or publishing this book or journal?
What do you know about the company or group? Do they have a
How stable is this information source?
Be aware that no one is keeping an archive of all the material
on the web. If the author changes the page tomorrow, your source has
disappeared. You may want to print and keep a copy of anything from a web site that you cite
in a paper. Someone who reads your paper might need to view the source
material that you used.