The macaques constitute a genus (Macaca) of gregarious Old World monkeys of the subfamily Cercopithecinae. The 23 species of macaques inhabit ranges throughout Asia, North Africa, and Europe. Macaques are principally frugivorous, although their diet also includes seeds, leaves, flowers, and tree bark. Some species such as the long-tailed macaque will supplement their diets with small amounts of meat from shellfish, insects, and small mammals. On average, a southern pig-tailed macaque in Malaysia eats about 70 large rats each year. All macaque social groups are arranged around dominant matriarchs.

Old World monkeys are primates in the family Cercopithecidae. Twenty-four genera and 138 species are recognized, making it the largest primate family. Old World monkey genera include baboons, red colobus and macaques. Common names for other Old World monkeys include the talapoin, guenon, colobus, douc, vervet, gelada, mangabey, langur, mandrill, surili (Presbytis), patas, and proboscis monkey.