    pop music (a term that originally derives from an abbreviation of "popular") is a genre of popular music, which originated in its modern form in the 1950s, deriving from rock and roll. the terms "popular music" and "pop music" are often used interchangeably, even though the former is a description of music which is popular (and can include any style). as a genre, pop music is extremely eclectic, often borrowing elements from other styles including urban, dance, rock, latin and country; nonetheless, there are core elements which define pop. such include generally short to medium-length songs, written in a basic format (often the verse-chorus structure), as well as the common employment of repeated choruses, melodic tunes, and hooks. so-called "pure pop" music, such as power pop, which has been described as mixture of hard rock and melodic pop music"power pop - significant albums, artists and songs, most viewed", allmusic, retrieved 28 september 2014. and tends to be more aggressive than pop rock,{{cite 
Pop_music Western_culture