Hyenas are any carnivorous animals of the family Hyaenidae. It has only four living species. It is the fifth largest biological family among carnivores and one of the smallest biological families among mammals. Despite their low diversity, hyenas are unique and vital components of most African ecosystems.

Although they are more similar to cats and ververids in phylogeny, hyenas are similar in behavior and morphology to canines in some ways. Hyenas and dogs are non treelike, coarse hunters who prey with teeth rather than claws. Both can eat fast and store food, while the calluses have large, blunt, non retractable nails on their feet, which are suitable for running and sharp turns. However, hyenas' grooming, scent marking, defecation habits, mating and parental behavior are consistent with those of other feline animals.

Spotted hyenas can kill up to 95% of food animals, while striped hyenas are largely scavengers. In general, although hyenas are known in popular culture for their timidity, they are known to kill large prey, such as lions. Hyenas are mainly nocturnal animals, but sometimes venture from their nests in the early morning. In addition to the highly valued hyenas in society, hyenas are not usually social animals, although they may live in families and gather to kill.

Hyenas first appeared in Europe and Asia in Miocene. They were formerly ververid like ancestors and then diversified into two different types: light hyenas and strong hyenas with broken bones. Although hyenas like dogs flourished 15 million years ago (a taxon has been colonized in North America), they have become extinct with climate change and the introduction of canines into Eurasia. Among the hyenas' bloodlines, only the insect eating hyenas survived, while the bone crushing hyenas (including the existing spotted, brown and striped hyenas) became the undisputed top scavengers in Eurasia and Africa.

Hyenas play an important role in the folklore and mythology of human culture in which they live together. Hyenas are often seen as frightening and disdainful and associated with witchcraft, as their body parts are used as ingredients in traditional medicine. In some cultures, hyenas are thought to affect people's spiritual lives, robbing graves and stealing livestock and children.