Pop music is a genre of popular music that originated in its modern form in the United States and United Kingdom during the mid-1950s. The terms "popular music" and "pop music" are often used interchangeably, although the former describes all music that is popular and includes many styles. "Pop" and "rock" were roughly synonymous terms until the late 1960s, when they became increasingly differentiated from each other. 

Although pop music is seen as just the singles charts, it is not the sum of all 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".

1. What terms are often mixed up?
2. Don't they mean the same thing?
3. What's the difference?
4. Are pop and rock the same?
5. Were they at one time?
6. When?
7. Who is the first male mentioned by name?
8. What does he think?
9. Does anyone agree with him?
10. Who?
11. Is anyone else mentioned?
12. Name?
13. Does he agree with Hatch?
14. What does he think?

Provide a numbered list of answers.
1. popular music and pop music
2. no
3. popular music describes all music that is popular, pop is it's own genre
4. no
5. sort of
6. until the late 1960s
7. David Hatch
8. that pop music is "a body of music which is distinguishable from popular, jazz, and folk musics
9. yes
10. Stephen Millward
11. yes
12. Pete Seeger
13. no
14. pop music is "professional music which draws upon both folk music and fine arts music"