Grooming is a very complited but important thing for certain cats.  For many cats, like my cats, tabbys, don't need to be groomed.  They naturally groom themselves.  This is called sheeding.  If you have a short haired cat, like a tabby, siamese, or many other types, your cat will shed its hair.  If you have a long haired cat, you must groom it.  Here is how to groom.  First, you need a cat hair brush.  You then gently stroke the brush across the cats fur but must always go from head to tail.  If you do not go from head to tail but the opposite, tail to head, your cat will get very mad on account that this hurts a cat a lot.  Whatever you do do not go from tail to head.  As you groom the cat, take the excess hair and dispose of it in a trash can.  If you leave the cat hairs around the house, they will get worn into the carpet because the cats don't like excess air around the house.  Do this grooming technique once a week in the fall and winter and twice a week in the spring and summer.  That is what grooming is.