Pop Art has two distinct classifications:
1) Art movement of the 1950s (early in UK. late in US)
2) Any sort of art inspired by popular culture
Now popular culture is simple; trends, movements; anything involving the masses. It can be from a fashion trend to a technological one. It is forever changing, continually moving forward as modernization never stops. For example, iPod is a part of popular culture because most of everyone uses one and it has inflence the lifestyle of the masses. It is popular.