Pop is a genre of contemporary music and very popular in the popular music scene. Pop music began in the 1950s and originated in rock and roll. The term does not accurately describe the genre of music or sound, but its meaning is very different depending on the time of its history and the different places in the world. In pop music, pop music is often distinguished from other genres by virtue of some artistic style, straightforward melodies, and some sections of the song that are repeated. Pop lyrics often refer to love, emotion, and other topics. Pop is a very diverse genre of music. Often pop music is classified by genre and by country or territory.