A monkey is any member of two of the three groupings of simian primates. These two groupings are the New World and Old World monkeys of which together there are nearly 200 species. Because of their similarity to monkeys, apes such as chimpanzees and gibbons are sometimes incorrectly called monkeys. Also, a few monkey species have the word "ape" in their common name. Because they are not a single coherent group, monkeys do not have any important characteristics that they all share and are not shared with the remaining group of simians, the apes.

Monkeys range in size from the Pygmy Marmoset, at 10 cm (4 inch) long (plus tail) and 120 g (4 oz) in weight to the male Mandrill, almost 1 metre (3 ft) long and weighing 35 kg (75 lb). Some are arboreal (living in trees), some live on the savanna; diets differ among the various species but may contain any of the following: fruit, leaves, seeds, nuts, flowers, insects, spiders, eggs and small animals.

Some characteristics are shared among the groups; most New World monkeys have prehensile tails while Old World monkeys do not; some have trichromatic colour vision like that of humans, others are dichromats or monochromats. Although both the New and Old World monkeys, like the apes, have forward facing eyes, the faces of Old World and New World monkeys look very different though again, each group shares some features such as the types of noses, cheeks and rumps. To understand the monkeys, therefore, it is necessary to study the characteristics of the different groups individually.

The name monkey may come from a German version of the Reynard the Fox fable, published in around 1580. In this version of the fable, a character named Moneke is the son of Martin the Ape. The word Moneke may have been derived from the Italian monna, which means "a female ape." The name Moneke persisted over time likely due to the popularity of Reynard the Fox.

Jam shok i ngushte me Mandin :)