The Impact Factor is a measure of the frequency with which the "average article" in a journal has been cited in a given period of time. It is one way scholars measure the relative importance of a journal within its field.
Finding highly cited authors can lead you to highly cited journals and articles.
Not sure if an article is scholarly or popular? Ulrichs has detailed information on more than 300,000 publications. Enter journal/magazine title in the search box and find your publication. Then, look for Academic/Scholarly in the Content Type field.