Threading is a form of hair removal using cotton or polyester thread originating from Asia. In more recent times it has gained popularity in western countries. Threading allows for a more defined and precise shape and can create better definition for eyebrows. It is also used as a method of removing unwanted hair on the entire face and upper lip area. Threading is not a good method for removing hair on arms or legs, as the hair in those regions is typically quite coarse and there is too much to remove.
When compared with waxing or tweezing, threading is much less painful when done correctly. Depending on the therapist/your tolerance/the time of the month threading feels like tweezing multiple hairs at at once. After threading remember to apply some aloe gel or cooling gel to reduce the redness. The redness would usually subside by an hour. Makeup around that region is also not advisable directly after doing the threading as you might irritate your skin and get an allergy reaction.
Threading is cheap and last longer than shaving so opt for threading if you have the option. Threading generally last about 5 – 6 weeks which is a major plus point for people with less time in on their hands. Threading also gives you your desired brow shape making it easier for you to draw your brows in the morning if you are the type to fill your brows.
Sources: http://www.cosmopolitan.com/uk/beauty-hair/advice/a33428/first-time-brows-threaded/
http://www.glamour.com/story/the-dos-and-donts-of-eyebrow-t