Chin hairs are like stars. You don’t always see them, but every so often they emerge to surprise you in all their bold glory.

Facial hair, of course, is no big deal, but we have always wondered what the deal is with that one thick, long hair that seems to appear out of nowhere, just begging to be plucked.

We took a break from staring at our faces in magnified mirrors to call on the experts. First and foremost, we wanted to know what makes those individual chin hairs different from our thinner, finer facial hair.

Dr. Heidi Waldorf, director of laser and cosmetic dermatology at The Mount Sinai Hospital, broke it down for HuffPost.

“These are terminal hairs versus the vellus hairs on the rest of the face,” she said. “Hair differs in its susceptibility to testosterone. Beard and mustache hair are more susceptible. Since [the chin is] considered a masculine area, when hair appears in that area in women, it is referred to as hirsutism.”

Hirstuism is a medical condition that is often caused by polycystic ovary syndrome and certain medications that cause excessive growth. But if you have just one or two terminal hairs that appear in the same place each time they grow, you can usually chalk it up to our unique, complicated bodies.

“Hair follicles have a mind of their own,” Angela Lamb, director of the Westside Mount Sinai Dermatology Faculty Practice, director of dermatology at the Institute of Family Health and an assistant dermatology professor at the Icahn School of Medicine at Mount Sinai, told HuffPost. “Sometimes one or more hairs will grow in thicker or fuller than others. This is the same reason why you may notice different hairs on your scalp that are curlier in some parts more than others.”

It’s not totally random, though. Like most other things in life, you have genetics to thank for the amount of hair that grows in on your face.