Bonnet Cleaning is really only seen in commerical areas. It is done with a rotary machine with a large absorbent pad. It sprays a solution on the floor and then the pad loosens and removes dirt.

Personally, I've never tried it or seen it in action, so I don't know how effective it is.  A lot of carpet manufactures are starting to require carpet to be steam cleaned to maintain your warranty.  I personally use a professional steam cleaninf company for my business.  When done with the right equipment steam cleaning does an excellent job of removing dirt and stains.

Thanks for your advice.