In this photo by Walker Evans depicts a building in New York during the Depression. This is an example of a short depth of field photo that I am really drawn to in my own photography. Buildings are a really good subject because there are so many textures, layers, and angles in a short amount of space that it still adds a lot of interest. In this particular photo there is also a lot of vintage typography in the signage as well as two painted pointed fingers on opposite sides of the door that creates a playful focal point for the viewer.
This is a photograph by Sebastião Salgado that shows a deep depth of field with a small structure in the foreground and a figure facing the distant sun over a hazy rolling ground in the distance. With this wider angle there is more movement and storytelling shown. The vastness shown makes the figures and structure seem all the more desolate. The sky and ground also fade into each other in midtones where as the figures are black and are clearly the characters in the story highlighted by the bright white sun.
These are good examples of short and long depth. But depth of field refers to focus. Short depth of field is when the focus is in the foreground and the background is out of focus. Long depth of field refers to foreground, midground and background, all in sharp focus.