The wide variety of sources examined for this research has informed our project on various scholarly opinions and arguments. Kim Kyle’s Los Angeles Times article “The Evolution of Music: How Genres Rise and Fall over time” argues that there are defined shifts in popularity between music genres over time, with some genres on a more oscillating scale and others much more dramatic. Similar to Kyle, the article “Understanding Media and Culture: an Introduction to Mass Communication” from the University of Minnesota argues that people’s preferred music genres change rapidly over time. Matthias Mauch (along with 3 other contributors) wrote the article “The Evolution of Popular Music: USA 1960 - 2010” which argues a similar point to Kyle and the University of Minnesota. Mauch’s article discusses that popular music in the USA changed due to specific cultural norms and likes. Overall, these three articles agree on the hypothesis that some genres of music are incredibly volatile and respond to cultural dynamics while others are more consistent over time. Rebecca Morelle’s article “Pop Music Marked by Three Revolutions in 50 Years” argues that pop music has evolved continuously since the 1960s in the USA, pointing to three distinct stylistic ‘revolutions’ occurring around 1964, 1983, and 1991. Evolver.fm’s article “What Makes a Hit Song? Science Tries to Find the Answer” argues that there are specific features that are common characteristics across all popular songs. They employ more of a scientific approach, analyzing BPM (beats per minute) and tempo. Daniel Silver’s article “Genre Complexes in Popular Music” argues that genre conventions exist that structure popular music, and these conventions differ across musical styles. Overall these articles examine more exact music engineering related reasons for why music becomes popular, along with noting explicit dates when noticeable popularity shifts happen. Interiano Myra’s article “Musical trends and predictability of success in contemporary songs in and out of the top charts” discusses the acoustic features of a song and how those features relate to the song’s popularity. Similarly, Alex Wilson and Bruno Fazenda’s article “Perception of Audio Quality in Productions of Popular Music” from the Acoustics Research Centre at the University of Salford, argues that the perception of a song’s quality can be affected by numerous factors such as loudness and dynamic range compression. In the book Soundtracks by John Cornnell and Chris Gibson, the authors summarize and track the landscape of popular music’s change over time. These three sources argue that acoustic features along with several other musical factors influence how a song becomes popular, and when a song becomes popular. Marc Hogan’s article, “Uncovering How Streaming Is Changing the Sound of Pop,” provides a very interesting insight into the current landscape of popular music, claiming that streaming services such as Spotify, have a large hand in shaping what people listen to based off of their recommendation algorithms. By the same token, Paul Resnikoff’s article “What Are The Most Popular Music Genres?,” explores general trends in the listening habits of America, showing not only what people are listening to but also how. Another article that ties in to America’s current soundscape is Eric Weisbard’s “Beyond Category? Never! The Game of Genres in Popular Music,” which is a critique of two books that discuss how communities create musical genres. These three sources offer a refreshing perspective as young music listeners continue to change the way people think about and listen to music. The final source on our bibliography is Sheila Whiteley and Jedediah Sklower’s Countercultures and Popular Music. The main point of this book is that one can trace the changes in popular music by analyzing the social trends of the time, particularly of the counterculture and their musical reaction to the social and political injustices of their day. Little to none contradictions exist in the literature we are using for our research. All sources to point to the central idea that music trends speak to historical progression. Scholars all agree on this change over time. Some questions still remain. Often songs that seem out of the usual prediction for hits make it to the top charts. Also, it would be interesting to further explore the role of new and emerging technology in the music space, and how this new tech is making it easier to produce music without the need of music labels and the traditional thru fare artists had to take back in time.