Whenever I tell anyone what I do for a living the first question I am asked is "Do you get bit a lot?". Of course I get bit, but there are so many different levels of dog bites that it's hard to answer that question with a simple yes or no. I think people group all bites into one category of aggressive behavior where the dog is looking to rip us to shreds.  Even my own children who are surrounded by dogs didn't understand the different ways dogs communicate through biting.  At first hearing "Clare bit me" was alarming and then when I watched the situation I saw that she was playing with them and in play was using her mouth but in no way inflicted harm or even used pressure.  Of course a dog has teeth that are pretty sharp, puppy teeth in particular, so it may hurt on our skin but it was not what I would call a "bite".  

There are times when a dog is playing and gets mouthy and their teeth may make contact with human skin, this isn't a bite, it's play.  Be sure to recognize the difference cause it can be disconcerting hearing your dog "bit" someone when what they were really doing was playing.  On the owner's part it is our responsibility to train our dogs not to be mouthy during play, instead divert that attention to a tug toy, or other appropriate toy to avoid any future problems with strangers.  Young dogs explore with their mouths just as babies do, so it will take some time, and even though it is cute now it will not be cute when your 12 wk old puppy is now full grown and can fit your whole forearm in his powerful jaws.  

The next type of "bite" is when the dog has told you several times he's not happy with your actions and has asked you politely to stop.  This is not play, but it is still a polite way for the dog to say to you, please stop.  They may put their teeth on you but there is no pressure no intent to cause harm, just them saying, hey!  Of course this can escalate to where they do begin to apply some pressure because you're not heeding their pleas.  For example, when I'm clipping a dogs toe nails, they may be ticklish or sensitive and not like their feet handled, let alone their nails clipped.  When I don't comply with their attempts at pulling their feet away or other tactics to escape the nail trim, they may start to lick or open their mouth and put it around my hand.  Now if you are not very fluent in speaking dog I would not try this and tempt fate, but often they are just going to put their mouth on you and then move away.  Sometimes owners see this and get flustered thinking their dog is aggressive.  This type of bite is nothing to worry about and the dog is just asking me to stop.  

Then there's the bites out of fear.  These are dogs who are afraid and feel they need to protect themselves before the perceived threat gets the best of them.  I do not think this is a character issue, but instead the dog needs some confidence boosting.  Being more socialized and exposed to different situations, slowly and with love and protection, not just thrown into a busy scene.  Instead, take your dog to a park where they can watch the goings on from afar.  Reward them for behaving nicely and reassure them that everything is fine.  You don't want to baby them because if they feel you are trying to protect them from something then they may become more nervous wondering what's about to happen.  If you know there's nothing to fear, then act that way and your dog will follow your lead eventually.  

Lastly there are the dogs who seem to enjoy being naughty and biting almost getting a thrill out of it.  These are the dogs you have to be wary of as they can bite when seemingly unprovoked.  This may be a character flaw that requires serious training, or it may be as a result of a rough upbringing.  A rough upbringing does not necessarily mean abuse, they could have spent their formative months with minimal human or other dog contact and so it makes them nervous to have to deal with them now as they do not know how to interact appropriately.  Or it could be that the dog is in pain and needs medical attention, this is especially true if the dog was never a biter before.  On the owners part it requires vigilance and responsibility when around other people.  A biter is not necessarily a lost cause but does require work so be sure if this is your dog, seek out a positive reinforcement trainer who can help this dog hopefully come out of this bad habit and if not can at the very least help the owner learn how to safely integrate this dog into society.  

Of course my experience is based mostly on dogs being groomed which is definitely a special circumstance.  Many dogs never bite or nip or put their mouth on people but when they're being tested at the grooming salon and people they're not totally familiar with are touching them all over and picking up their paws and holding their faces and have these strange sounding clippers going all over them it is a different story.  People ask me if we do "bad dogs", and I say they're not bad dogs, they're just telling me they're not happy.  Plus the feisty ones keep us on our toes.  Of course if they are too stressed then I cannot groom them but for the most part I enjoy working with the difficult dogs and joining forces with their parents to help rehabilitate them into a more confident grooming experience.  Its hard to sit back and try to assess what kind of bite you or your kids may be experiencing from your dog, but just knowing that not all bites are savage attacks to end our lives is helpful.  Biting is a form of communication.  Not one we try to encourage, but don't immediately label a dog as "bad" just because someone claims he "bit" them.