What is the difference between an IS camera lens & a VR camera lens?

I have found that cannon uses is & nikon uses vr. But what's the difference?

The name only. Image Stabilization or Vibration Reduction. Same type of critter.

The difference between a Big Mac and a Whopper.

Pentax, Sony and Olympus build similar systems into their bodies, rather than the lenses.

Nomenclature.

They're the same thing IS is Image Stabilization, while VR is vibration reduction, but they both work pretty much the same.

Just different brands trademarking different names for the same kind of thing. Sigma's version is OS (Optical Stabilization), and Tamron's is VC (Vibration Compensation).