Pop is a genre of popular music that originated in its modern form during the mid-1950s in the United States and the United Kingdom.
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Rock and pop music remained roughly synonymous until the late 1960s, after which pop became associated with music that was more commercial, ephemeral, and accessible.
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Identifying factors usually include repeated choruses and hooks, short to medium-length songs written in a basic format (often the verse-chorus structure), and rhythms or tempos that can be easily danced to. Much pop music also borrows elements from other styles such as rock, urban, dance, Latin, and country.
Pop Music – Wikipedia, the free encyclopedia