Some camera bodies, such as the F/N80, D100, F3 and older manual bodies, require the mechanical cable release and sometimes additional attachments (i.e. F2 bodies) whilst others, such as the F/N90x, F100, F5, D1(x/H), etc…, require the electrical/electronic 2-pin or 10-pin cable releases. 

There are a few newer bodies, such as the F/N65 and F/N75, that will only work with a infrared remote control unit. Another option to the cable release (if you do not have one or forgot to bring it along to your shoot) is to use the camera’s built-in self-timer instead. 

The whole purpose of the off-camera triggering is to minimize accidental camera-shake when tripping the shutter. If however you were handholding the camera, it would be advisable to use the fastest possible shutter speed allowable as well as proper breathing and shutter-release techniques to reduce the amount of camera-shake during the shot. 
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