Although many of the library's databases provide access to all types of sources, your instructor will want you to use quality, peer-reviewed, academic literature found in journals.
These journals (also known as serials or periodicals) publish the world's most recent peer-reviewed research in all disciplines, whereas popular 'magazines' are primarily designed to entertain as well as inform the general public for commercial profit.
Getting to know the differences between these sources is important! If you are unsure if a journal is peer reviewed, check Ulrichsweb. It is the definitive source that lets you know what type of journal (serial, magazine, periodical) you are reading by 'content type'.
Bibliometrics are used to rank academic journals. These rankings are important for things such as building library collections, or academic career advancement.
To learn more, check out the following: