The gray wolf is also called the common wolf or Canis lupus. There used to be a lot more wolves in the world than there are now, but there are still enough around so that they are not considered to be a threatened species.
A wolfdog (also called a wolf–dog hybrid or wolf hybrid) is a canid hybrid resulting from the mating of a wolf and a dog. The term "wolfdog" is preferred by most of the animals' proponents and breeders because the domestic dog was categorized in 1993 as a subspecies of the gray wolf. The American Veterinary Medical Association and the United States Department of Agriculture refer to the animals as wolf–dog hybrids. Rescue organizations consider any dog with wolf heritage within the last five generations to be a wolfdog, including some established wolfdog breeds.
As of 1998, the USDA estimated the approximate population of wolfdogs to be around 300,000 in the United States , with some other census studies estimating the population could be as high as 500,000. In first generation, gray wolves are most often crossed with wolf-like dogs for an appearance most appealing to owners desiring to own an exotic pet.