There are several types of sources but the ones you will most often come across in your schoolwork are popular sources and scholarly sources. When writing for your classes, it is important to use scholarly sources. Let's review the differences.
| Popular Sources | Scholarly Sources |
|---|---|
| The audience is the general reader. | The audience is typically scholars, researchers, and students. |
| Do not typically include any citations. | Include citations and a reference page or bibliography. |
| Written on any topic the author wishes. | Written on a topic within the author's subject specialty. |
| Are not reviewed by subject experts. | Are reviewed by by the author's peers, those who are subject experts. |
Scholarly sources are almost always peer reviewed sources and so those terms are used interchangeably. Your instructor may ask for either one but ultimately mean that they want sources which have been peer reviewed.
Peer reviewed sources have been read and verified by experts in the field which the source is about. For instance, a peer reviewed article about the treatment of lung cancer would be read by experts on lung cancer. Those experts would verify that the research for the article was conducted following the standards of that field.