Humans and monkeys are both primates and have many similarities. The hair of both mammals is similar but also have distinct differences. There are many different kinds of monkeys, most of which display slightly different hair types.
Even though monkeys appear to have the same strands of hair that are on humans, monkeys actually have fur (something humans do not have). Fur usually grows to a certain length and then doesn't grow any more.
Some areas of human hair, especially on the head, will not stop growing. These hairs must be trimmed regularly. Monkeys have no reason to trim their fur, since it stops growing at reasonable lengths.
The fur on a monkey's head isn't any different than the hair on the rest of its body, whereas the hair on the head of a human grows much longer and thicker than anywhere else on the body.
While humans do have very small and thin hairs over their entire body, it isn't nearly as prominent as the fur that covers the body of a monkey. Men usually have more visible hair on areas like the chest, face and back (compared to females), but both male and female monkeys have long fur everywhere.
Humans have a special area of hair around their pubic region which is coarse. Since monkeys have hair over their whole body, it doesn't change texture in their pubic region.