David Hockney - This mural is made up of photographs. Even though the photos don't go together they still look really effective together. As I do photography I could take the photos, put them together and paint them.
The numbers on the arms are from prisoners of Nazi concentration camps. The numbers replaced their names while at the camps and they were tattooed on so that they could be easily tracked by the Germans. This is why we study history. So this never happens again.