what you should do, to dogs definitely,(it helps with other animals too) is to lower a hand toward them, present the back of your hand and allow them to sniff i

what you should do, to dogs definitely,(it helps with other animals too) is to lower a hand toward them, present the back of your hand and allow them to sniff it, only then should you attempt to stroke the dog (if it snarled at the offered hand dont stroke it), and when you do stroke it, dont go straight for the top of the head. Crouching down to its height could expose you to worse injury as you are now putting your face and throat much closer to the animal. These are the instructions I give my children, who love animals and are used to dogs and want to pet every dog they see.