Precursor to Art Photography
Although critic and philosopher Walter Benjamin heralded Atget as a precursor of Surrealist photography (where his influence is definitely apparent, especially if you consider the images containing interesting juxtapositions caused by reflections in shop windows), he was even more important as an influence on documentary photography and a precursor of the Modernist movement.
Documentary photographers like Bernd and Hilla Becher were certainly affected by the way Atget's seemingly simple images could hold more meaning than the sum of their subject matter would indicate, and they took the approach of photographing structures in a simple, straightforward manner even farther in their own work. Thus, Atget became a hero of the "straight photography" movement, too.
There is some debate about whether or not the elements that make Atget's work "art" today were intentional or simply accidental results of the way he shot. There is doubt, for example, that the juxtapositions created by reflections and the psychological affects of slightly off-centre framing seen in many of his images were deliberate. Berenice Abbott, however, pointed out that Atget was working with a view camera and very large glass-plate negatives (the standard size was 18 by 24 centimeters, or not quite 8 by 10 inches). It's simply not possible, she said, to frame and focus an image on a ground glass viewfinder of that size without noticing pretty much everything in the image.
Interestingly, though smaller cameras were coming into wider use at the time, and Man Ray even offered Atget the use of a Rolleiflex, Atget refused to use any other equipment. Small cameras, he said, worked faster than he could think. And besides, it was partly the limitations of his equipment that allowed Atget to create images that are uniquely his.