It always irks me when someone on TV or IRL calls a chimpanzee a monkey considering chimps are our closest living primate relative.  There are hundreds of species of primates, Homo sapiens being just one.  We break these hundreds of species into three groups (and of course many more subgroups, but for the sake of simplicity):  Prosimians, Monkeys, and Apes.

All of us primates have opposing thumbs and stereoscopic vision but beyond that the differences can be numerous.

Prosimians are very diverse with some of the most unique features such as a tooth comb, grooming claw, cute little wet nose, etc.  They are mostly nocturnal and eat insects.  Examples of prosimians are lemurs and aye-ayes.

Monkeys are further broken down into Old World and New World.  They are usually diurnal, have tails, and all but two have nails on their fingers.  They mostly live in tropical places and live off of forest vegetation.  Examples of monkeys are Capuchin, Spider, and Howler.

Apes do not have tails, are diurnal, and have nails.  They also have less hair on their faces.  Most apes except humans (and certain groups of chimpanzees) live off of forest vegetation and live in a tropical or subtropical environment.  Humans have adapted to live in just about any climate.  Examples of apes are orangutans, chimpanzees, gorillas, and humans.

Sigh.  I miss this stuff…

Reference:  Memory – so hopefully I didn’t make too many errors.