Dogs are domesticated form of the Wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The domestic dog has been one of the most widely kept working and companion animals in human history. Amongst canine enthusiasts, the word “dog” may also mean the male of a canine species, as opposed to the word “bitch” (the female of the species).
Dogs are quickly became ubiquitous across culture in all parts of the world, and was extremely valuable to early human settlements. For instance, it is believed that the successful emigration across the Bering Strait might not have been possible without sled dogs. Dogs perform many roles for people, such as hunting, herding, protection, companionship, and, more recently, assisting handicapped individuals. Currently, there are estimated to be 400 million dogs in the world.