Relation Between Aperture and Depth of Field of Digital SLR

Let's take a look at some examples of how aperture settings affect depth of field. By observing the image, we can easily understand that, how the aperture setting can affect the depth of field.

Basically, when the aperture is high then the focused object will be clearer and the others will be blurry. That means, there will be less depth of field. On the other hand, the less the aperture is, the more the depth of field will be. That is, other objects will be clearer.