I've just got back from doing some work in Canberra. The hours were very long and I had little time to post. All I could manage to post was the odd image, mostly from the street work of Harry Callahan, which I juxtaposed with the English landscape work of Fay Goodwin.
The point of posting Callahan's street work was to highlight the way that a visual langauge was formed based on the commonplace during the mid-20th century.
Around this time Robert Rauschenberg was working:

Robert Rauschenberg, Rebus, 1955
What he found significant about photography was not the art photography in the gallery, but the actual phenomenon of photography: the snapshot, the advertsiing photography, the news photograph. These were the folk images----the habitual idiom--- of contemporary consumer culture.
Rauschenberg incorporated them into his work:

Robert Rauschenberg, Untitled, 1963
Many of these photographs had been reduced by multiple reproduction to the status of a commodity in industrial society. Rauschenberg incorporated such “found” materials as advertisements into loose, abstract compositions:

Robert Rauschenberg, Brace, 1962
In the process he created a visual urban language.