The title should tell you enough I guess. Can't really add much about the site then what the name would give you as a mental image. It leaves a big impression though.
But I can add something about Photography:
1) Didn't take a lot of pictures, but others did. I really don't understand people who take pictures in the classic "I was here" pose anyway, but in a concentration camp?!
They stand with one hand on their hip, smiling, in front of some crematorium and let one of their idiot friends take a picture. A real "look at me being here!" kinda thing. Seriously... I don't get that.
2) There were a couple of photos of the camp from after the liberation, taken by the Russian Red army. I tried to get the information from our guide -she didn't know or understand me- but I wondered about these: I guess film wasn't too easy to get in Russia during the war, and a camera doesn't sound like a really standard kit for a soldier.. Where there special photography-teams? Maybe military intelligence?