POP MUSIC VS CLASSICAL MUSIC

During the 1950's."It [pop] was created as a synonym of "rock-n-roll" during the birth of the rock era in the 1950's in order to separate the then-new, then-controversial form of music from the jazz, gospel, big band, and classical music that had come before it." - from
http://en.wikipedia.org/wiki/Pop_music

Popular music, sometimes abbreviated as the genre pop music, is music belonging to any of a number of musical styles that are (at least in their heyday) broadly popular. Broadly, any music that is a part of popular culture, including classical, folk, or other music that has entered popular culture. Popular music dates at least as far back as the mid 19th century.
http://en.wikipedia.org/wiki/Popular_music

The Classical period in Western music occurred in the second half of the 18th century. Although the term classical music is used as a blanket term meaning all kinds of music in a certain tradition, it can also occasionally mean this particular era within that tradition. Commonly given beginning and ending dates for the period are 1750 and 1820, although there was considerable overlap at both ends with preceding and following styles, as was true for all musical eras. Actual beginnings of the Classical style during this period (1730-1760). The term applies to music going back to 425.
http://en.wikipedia.org/wiki/Classical_music_era