Threading is an ancient Asian hair removal technique which, in recent times, has gained popularity in Western countries. During threading, a thin (cotton or polyester) thread is doubled, twisted and then rolled over areas of unwanted hair, plucking the hair at the follicle level. Unlike tweezing, where single hairs are pulled out one at a time, threading can remove short lines of hair. Advantages cited for eyebrow threading, as opposed to eyebrow waxing, are that it provides more precise control in shaping eyebrows and is gentler on the skin since no heat or chemicals are being applied. It can however be painful as several hairs are removed at once.