[MyPix]

in laymans terms,

the point you focus at is split into thirds,
two thirds are in focus behind the shot, and one third in front
so if you focus at 10 meters away, and at the right depth of field ( blured/unblured) , it could be 2 meters behind and 1 meter in front in focus, and the rest is blurred,

now,, the higher the Fstop also known as aperature the smaller the distance between the focusing points, the larger the fstop,the greater the distance and more is in focus, another way of saying it would be that the depth of field is bigger.

this can be set on ' simple ' cameras by choosing the shooting options , for example, you will have a portrait mode, closeup mode, and mountain( landscape ) mode,
the closeup and portrait will give the blurred effect on anything around 3-7 meters away, the landscape mode will have everything in focus ( pritty much )

hope this helps

MyPix