MODERNISM

Compare and contrast Andy Warhol's and Richard Hamilton's respective definitions of Pop Art. What works would you argue most reveal the "preoccupations" of Pop?  Also, what is Pop Art a reaction against? What movement is it obviously indebted to and how?  How is this movement particularly representative of the 1950s and 1960s?  And what artists, in addition to Warhol and Hamilton, best exemplified the Pop (or, later, Op Art) perspective?