The dog, or domestic dog (Canis lupus familiaris, formerly Canis familiaris), is the domesticated and bred form of the gray wolf (Canis lupus). It belongs to the class of mammals and the family of canids.
The dog is the oldest domesticated animal of humans. In the early stages of domestication, dogs were useful as warning guards and scavengers. Over time, they have also been used as draft animals, herders, and hunting companions. Today, their roles have expanded to include tasks such as drug detection, guiding, hypo-alerting, and rescue operations. Many of these roles utilize the dog’s exceptional sense of smell.