Pop music originated in the 1930s in the US with the emergence of swing music performed by big bands and artists like Frank Sinatra and Bing Crosby. In the 1950s, rock and roll became popular, featuring a louder sound and themes of rebellion and love. Pop music refers broadly to popular music genres enjoyed by younger audiences, as measured by sales on music charts that rank the top 40 or 100 songs.

1. Pop Music History
Pop music is an abbreviation of 'popular' music, it started in the US, in the 1930's
with a new type of music called swing. Frank Sinatra and Bing Crosby sang with
big swing bands and then became solo artists later on. In the 1950's, rock and
roll emerged, it was louder and more exciting with songs about rebellion and
love. Although, before, pop music was used to describe popular music which
included all genres of music. Popular music is very vocal, and it usually appeals to
a younger audience, but still a very large audience. The popularity of pop music
songs is measured by the charts, which basically rank the top 40 or top 100 pop
songs based on how many copies it has sold (either CD's, iTunes, or Spotify).