 From about 1967, it was increasingly used in opposition to the term rock music, to describe a form that was more commercial, ephemeral and accessible.In contrast rock music was seen as focusing on extended works, particularly albums, was often associated with particular sub-cultures (like the counterculture of the 1960s), placed an emphasis on artistic values and "authenticity", stressed live performance and instrumental or vocal virtuosity and was often seen as encapsulating progressive developments rather than simply reflecting existing trends.Nevertheless, much pop and rock music has been very similar in sound, instrumentation and even lyrical content.