There are places on this earth where workers are given almost no food or water, stacked in fecies and mud infested cages and die before the age of 3 or 4. Are you horrified yet? This is what happens in the world of the "Puppy Mill". The poor dogs and bitches are the workers and the "breeders" (if you would even call them that) are the all powerful factory owners.
Puppy Mills do exactly what the name implies, produce puppies. They do not do this to improve these breeds. They do not breed to produce seeing eye or police dogs either. They breed for money. They don't spend time or money testing for hereditary problems or even checking if the puppies produced are free of congenital problems. They breed 6 month old bitches (female dogs) of poor quality every time they come in heat. This is on average, every 6-9 months. A bitch will have had around 6 litters by the time she is 4. That isn't even the worst part. When reptable breeder breed their bitches they are pampered and cuddled, given the best food and soft places to sleep. In a puppy mill a bitch will have to drink from mud puddles, fight other dogs for food and try to keep her puppies warm from wind and snow when all she has around her is a 5 by 5 foot cage. This dosen't only happen to the females when they are pregnant. The males and unpregnant bitches live in the same conditions. No one ever gives them a hug or a pat on the head. Instead they have food bowls flung at them and water dumped on their heads.
Puppy Mills sell their dogs to other puppy mills, brokers and pet shops. Sometimes they will even sell through the newspaper. Pet shop puppies ALWAYS come from a puppy mill or backyard breeder. A backyard breeder is a puppy mill on a smaller scale. They are inexprienced people who want to make a couple bucks and care less if the puppies they breed go to good homes or if they are filled with hereditary problems. Just because a breeder is registered with the CKC, AKC or any other kennel club does not make them a reputable breeder.