They serve different functions depending on the part of the body.

On the head, they protect from solar radiation and cold.

On the eyebrows, they prevent sweat from flowing down and reaching the eyes.

In the ears, the hair and wax act as protection, keeping out dirt particles, small insects, and bacteria.

In the nostrils, the hairs function as a natural filter that prevents dust particles from entering the respiratory tract. This is why the famous “booger” forms on the outside of the nose.

In the armpits, the hair protects the skin from friction between the arms and the body.

The eyelashes protect the eyes.

In the intimate region, in women, they act as a primary protection of the vaginal canal against the entry of substances that can cause infections or diseases. For men, they no longer have any function today, but in the past, they served to protect from the cold.

As for the other hairs we have on arms, legs, back, etc., many scientists believe they are just a legacy from our ancestors who were much hairier.