Although much of the music that appears on record charts is seen as pop music, the genre is distinguished from chart music. Pop music is eclectic, and often borrows elements from other styles such as urban, dance, rock, Latin, and country; nonetheless, there are core elements that define pop music. Identifying factors include generally short to medium-length songs written in a basic format (often the verse-chorus structure), as well as common use of repeated choruses, melodic tunes, and hooks.
David Hatch and Stephen Millward define pop music as "a body of music which is distinguishable from popular, jazz, and folk musics". According to Pete Seeger, pop music is "professional music which draws upon both folk music and fine arts music". Although pop music is seen as just the singles charts, it is not the sum of all chart music. The music charts contain songs from a variety of sources, including classical, jazz, rock, and novelty songs. Pop music, as a genre, is seen as existing and developing separately. Thus "pop music" may be used to describe a distinct genre, designed to appeal to all, often characterized as "instant singles-based music aimed at teenagers" in contrast to rock music as "album-based music for adults".
Pop music continuously evolves along with the term's definition. According to The New Grove Dictionary Of Music and Musicians, popular music is defined as "the music since industrialization in the 1800s that is most in line with the tastes and interests of the urban middle class." The term "pop song" was first recorded as being used in 1926, in the sense of a piece of music "having popular appeal". Hatch and Millward indicate that many events in the history of recording in the 1920s can be seen as the birth of the modern pop music industry, including in country, blues and hillbilly music.
According to the website of The New Grove Dictionary of Music and Musicians, called Grove Music Online, the term "pop music" "originated in Britain in the mid-1950s as a description for rock and roll and the new youth music styles that it influenced". The Oxford Dictionary of Music states that while pop's "earlier meaning meant concerts appealing to a wide audience ... since the late 1950s, however, pop has had the special meaning of non-classical mus, usually in the form of songs, performed by such artists as the Beatles, the Rolling Stones, ABBA, etc". Grove Music Online also states that "... in the early 1960s, 'pop music' competed terminologically with beat music , while in the USA its coverage overlapped (as it still does) with that of 'rock and roll'".
From about 1967, the term was increasingly used in opposition to the term rock music, a division that gave generic significance to both terms. Whereas rock aspired to authenticity and an expansion of the possibilities of popular music, pop was more commercial, ephemeral and accessible. According to British musicologist Simon Frith, pop music is produced "as a matter of enterprise not art", is "designed to appeal to everyone" and "doesn't come from any particular place or mark off any particular taste". It is "not driven by any significant ambition except profit and commercial reward ... and, in musical terms, it is essentially conservative". It is, "provided from on high (by record companies, radio programmers, and concert promoters) rather than being made from below ... Pop is not a do-it-yourself music but is professionally produced and packaged".