Depth Of Field

In general

A. The closer you are to a subject the less depth of field you will have.
B. The wider your aperture the less depth of field you will have.

DOF                                                MORE                                                                                        LESS

Aperture Setting                           F22                                                                                               F1.4

Focal Length                                Wide Angle                                                                               Telephoto

Shooting Distance                     Far away                                                                                     Close-up

Hyperfocal Distance.

The point at which you should focus to get the maximum depth of field in your photograph.

Depth of field extends 1/3 in front and 2/3 behind where your focal point is.