"Those are the pilar cysts on the scalp," Dr. Sandra Lee, MD, (a.k.a. Dr. Pimple Popper ) explains. The reason you've probably seen an explosion of these videos on her YouTube channel as of late: "They are really common, and some people have more than one. They are fun because they're so easy to do — it's like getting to take a little break at work. It only takes 10 minutes."