All monkeys are members of the suborder Haplorrhini, which also includes apes and humans. Monkeys are also members of the kingdom Animalia, the phylum Chordata and the order Primates. The family, genus and species depend on the type of monkey, as there are 260 species of monkeys with unique classifications.
Monkeys come in two parvorders, which include the New World monkeys, or Platyrrhini, and the Old World monkeys, or Catarrhini. New World monkeys are arboreal and prefer to live in trees, where they make use of their characteristic prehensile tails. Many Old World monkeys lack prehensile tails and live semiterrestrially, spending most of their time on the ground and a small amount of time climbing trees.