Prong collars must never be turned inside out (with the prongs facing away from the dog's skin), as this may cause injury against the body and head.  Plastic tips are occasionally placed on the ends of the prongs to protect against tufts forming in the fur or, in the case of low quality manufactured collars with rough chisel cut ends, puncturing the skin. Like the slip collar, the prong collar is placed high on the dog's neck, just behind the ears, at the most sensitive point.
In the twentieth century, formalized dog training originated in military and police applications, and the methods used largely reflected the military approach to training humans. In the middle and late part of the century, however, more research into operant conditioning and positive reinforcement occurred as wild animal shows became more popular. Aquatic mammal trainers used clickers (a small box that makes a loud click when pushed on) to "mark" desired behavior, giving food as a reward. The change in training methods spread gradually into the world of dog training. Today many dog trainers rely heavily on positive reinforcement to teach new behaviors.
Dog training shouldn’t wait until you’re having behavior problems. If you get a new puppy, start from the beginning with professional training to give both you and your puppy the tools you need for a healthy relationship. Dog training is as much about teaching the owner how to interact with their new dog as it is about the dog learning to behave. Puppy training can start as early as eight weeks old. Trainers who offer puppy training programs may works specifically with dogs between the ages of 8 and 18 weeks old. Trainers can teach owners about potty training and how to deal with accidents, working with separation anxiety, and training your pooch out of destructive behaviors like chewing, biting and demand barking. Puppies will start to learn to walk on-leash and other basic skills.