"Pop culture" is a phrase that refers to all of the entertainment and news that most people in a society know about. Pop culture includes information about celebrities' lives, ideas from popular books, familiarity with songs on the radio, and so on. "Pop culture" can be used as a noun:
His films have had a huge influence on not only the movie industry, but on pop culture as a whole.
Or it can be used as an adjective:
He was a pop culture icon of the late '70s.