Steichan and Arbus
Steichan has obviously an eye for composition and like strong contrasts. His pictures seems to concentrate more on his idealized view of the subject or maybe that's how the subject really wanted to be seen. It tells us about the person photographed but unlike Arbus, we do not feel that it could be someone in the street, it has a very strong artificial look. He uses all kind of lighting but even if it's soft he seems to still make it look dramatic. The subjects are placed to interact with their environment, providing an interesting composition in most of the pictures. I think the pictures are successful especially for people who are fans of dramatic, elegant and simply composed pictures. They are all pleasing to the eye at first sight. In my opinion, his style is mostly used today by fashion photographers for big magazines but it is also easy to see that it inspired Penn, a very good and known photographer.
Arbus' style is very different from Steichan but they both do portraits. Her approach is going further than the superficial look of her subjects. We feel closer to the subjects as we may see them in a different way than Steichan's subjects. The lighting (if not outside) is often very harsh and coming from a flash a bit off-camera. The pictures are taken "on the moment" and it is easy to see in the facial expressions of the subjects. The photos are not classical like Steichan's pictures; they are often weird and we might think more while looking at them. Some of them are also less interesting at first sight; we have to study them for a longer time. The environment seems less important for her too as most of the pictures the subjects are really close to the camera. Overall, her pictures feel less "staged" and we might feel closer to the subjects; that's why some people might appreciate these. It probably also inspired Witkin, who emulates old pictures and does strange portraits.
Cartier-Bresson and Evans
Henri Cartier-Bresson is probably the best photojournalist of all time and he is the creator of this type of photography. His pictures have a very strong composition and are almost all perfect. He used natural lighting because he was wandering around and taking pictures. That is why some people appreciate his pictures because we feel that we see what's going on but it is like if there wasn't any photographer present. It is mostly pictures of everyday life and he focuses on strong compositions, not directing the subjects at all. There is always a relationship between the subjects and their background, making a strong composition. I think Bresson's pictures inspired pretty much every photojournalists out there since we can always see a bit of his work in every good photojournalist work. Today, Bresson's style can be seen in photographers such as Alex Webb and probably many others.
Walker Evans is another very known photographer of that era. His work, in contrast with Bresson's, is more photo-documentary style. The main difference in my opinion between these two is that Evans seems to have met his subject and make them pose a bit. The pictures feel like they are a record of the past; that they are less about the composition and everyday life. We can see through the subjects, we can try to figure out who they are; they are more personal pictures. Both photographers work with natural light and taking pictures of people. Evans seems like a less technical photographer, more like he wants to give a message in every pictures and that is why I guess people appreciate his work. I don't know a lot about Steve McCurry a lot but his pictures reminds me a lot of Walker Evans too, proving that Evans was probably a source of inspiration for great contemporary photographers.