A pilar cyst (also known as a trichilemmal cyst), according to Dr. Pimple Popper's YouTube page, is basically the same as an epidermoid cyst, only slightly firmer and more "mobile." And ninety percent of them occur on the scalp, which is just where this cyst that Dr. Sandra Lee (the internet-famous dermatologist who goes by Dr. Pimple Popper) removed was located.
Dr. Pimple Popper's patient reveals that he's had the cyst for about 10 years, but since he's got thick hair, it's not terribly noticeable. In fact, it's his wife who wanted him to get it removed.
Dr. Pimple Popper debates whether or not to try to remove the pilar cyst whole or squeeze it, since she wants to keep the incision as small as possible. She ends up cutting it open because it's just too big to pull out whole. Horn no more!