Nikon D40 - Manual (Page 52)

40 Reference: P, S, A, and M Modes/Mode P (Programmed Auto)
Mode P (Programmed Auto)
In this mode, the camera automatically adjusts shutter speed and aperture for optimal
exposure in most situations. This mode is recommended for snapshots and other situations
in which you want to leave the camera in charge of shutter speed and aperture.
To take photographs in programmed auto:
Flexible Program
In mode P, different combinations of shutter speed and aperture can be
selected by rotating the command dial (“flexible program”). Rotate the
command dial to the right for large apertures (small f-/numbers) that blur
background details or fast shutter speeds that “freeze” motion. Rotate the
command dial to the left for small apertures (large f/-numbers) that
increase depth of field or slow shutter speeds that blur motion. All com-
binations produce the same exposure. While flexible program is in effect,
a indicator appears in the viewfinder. To restore default shutter speed
and aperture settings, rotate the command dial until the indicator is no
longer displayed, choose another mode, or turn the camera off.
1 Rotate the mode dial to P.
2 Frame a photograph, focus, and shoot.