Popular music can be studied academically by defining it, examining why it should be studied as part of higher education, and analyzing its history, production, consumption, and social impact. Key areas of focus include the development of the popular music industry; critiques of mass culture theory which viewed audiences as passive; and sociological analyses of genres like rock music and how they relate to youth culture. Academic study has grown since the 1970s and now includes departments, centers, and methods for analyzing popular music's musical and extramusical elements.