#Depth Of Field
Depth of field refers to how much of an image is in focus, specifically the distance between the nearest and farthest in-focus parts of an image. Images with a shallow depth of field exhibit a lot of out-of-focus area while images with a deep depth of field can have nearly everything in focus. Depth of field is related to aperture. Larger apertures (smaller f numbers) will leave less in focus - they give a shallow depth of field. Smaller apertures (larger f numbers) leave more of an image in focus - a deeper depth of field.