Of all of the dog behavior problems there are, biting is probably the most serious. If your dog pees on the rug, runs away, or goes on the couch it probably will not be a big deal. If you dog gives someone a serious bite, however, many communities require that it be put down. Dog biting problems can literally mean the end of your dog's life, so it is important to train your dog to never bite anyone.
Of course, puppy biting problems are normal. When puppies are teething, they naturally chew on everything and everyone. Although a puppy can give you a nasty enough bite to break the skin, you probably will not be seriously injured by anything your puppy dog can dish out. Nonetheless, teething is probably when you should start tackling your dog biting problem.
Training does not mean that you have to be harsh or met out some cruel punishment. All you have to do is tell him a firm "No!" when he takes a hard bite on you. Use phrases like "Bad Dog!" or something that has the tone of reprimand to let him know that you are hurt from his bite.
Most dog biting problems have a physiological cause behind them. You see, dogs do not only bite when they want to hurt something. They bite something if they want to hold onto it, they bite to play, and they bite as a way to warn people or other dogs do not go any further. The problem is that dogs have thicker skins than people. Your dog thinks of you as just another dog, so he can easily bite through your skin accidentally. If you don't address the dog biting problem while he is still a puppy, it can become serious. If you do train him not to bite too hard, he will grow up to be a great pet.
Of course, some dog biting problems occur because of aggression. You might just have a temperamentally difficult dog that gets angry and tries to hurt. If this is the case, you really need to send him to obedience school. These sorts of dog biting problems often lead to another dog being seriously injured, or even a person being hurt.
You have to take this problem very seriously and take steps to find the best help. Getting help from professional dog trainers are probably the only option to solve this problem.
If you have a pooch with biting problems in your neighborhood, the best defence is to be ready with a bottle of pepper spray that is specially formulated to combat biting dogs. Never hesitate to use the pepper spray if any dog tries to bite you. Or, you could opt for a friendlier approach by offering a beef jerky but only if you feel safe approaching the dog.