How can you tell if your source is peer-reviewed or popular? In addition to some of the techniques mentioned in the below video, you can look up the title of your source in Ulrich's Web. This resource will tell you specifically whether your source is peer-reviewed or popular.
Examine your information with the following points in mind. These tips work well for evaluating articles, books, & web resources.
When was the information written? Does it matter to your research if the information is current, or is older information also useful?
Does the information answer your question and meet your requirements? Is it entirely about your topic or are there just a few sentences about your topic? Is the information geared toward your level; is it too advanced or too elementary? If there is an abstract, scan the abstract. Does the description match your topic?
Who is the author/creator? Does he/she have a background that would suggest knowledge of the topic? Is the author associated with a reputable organization? Is contact or biographical information provided?
Where does the information come from? Is it backed up by evidence or just opinion? Is it substantiated in other sources? Are there misspellings and grammatical errors?
Why was the information written? To inform? To persuade? To sell? Are the intentions of the article made clear? Is the information presented objectively? Are there any biases present?
Read more about this evaluative process, also known as the CRAAP test.