Vibration Reduction (VR) is an important technology developed by Nikon for its lenses to somewhat counteract for camera shake when a photographer takes a picture. It is analogous to anti-shake in compact cameras that we see in the market.
Naming the technology differently, Sony has its super steady-shot built into its alpha series dSLR and not in the lenses. There is certainly room for debate whether anti-shake should be built into the lens or into the camera body.
See here for an introduction to vibration reduction by Nikon.
