You may ask ", Why groom a cat?"  Some cats do not spend as much time licking or preening, as they should.  The type of cat, and length of coat, definitely help determine how often your cat needs groomed.  There are special tools and shampoos designed to help reduce shedding in cats.  Another option is to have the cats' coat "clipped" shorter (especially beneficial with Persians and Himalayans).  Most cats have a double coat, and matting often occurs when the shedding process happens.  Cats ears need cleaned to help reduce wax buildup and remove dirt.  The nails should be trimmed monthly and their teeth should be brushed on a regular basis to avoid tarter buildup.  Lastly, and most indelicately, a kitty's rear might need the hair trimmed around it and cleaned up.