Furminator removes dead undercoat. It is basically part of a blade with a handle. Before it was developed, and still, many groomers simply card the dog's coat with a 30 blade. Does the same thing. It does not cut coat, simply pulls out dead hair. Works great, but caution needed so as not to irritate the skin.
My Mom and Dad have pugs and they shed like crazy!! I bought the FURminator for them and it seems to pull off the dead undercoat. It works wonderfully and reduces the amount of shedding that happens on clothes, couches and carpets down quite a bit. I would definitely recommend buying it!