Eyebrow threading is a technique for shaping eyebrows that originated in India and the Middle East. It involves using a thin cotton thread to pull hairs out from the root. The thread is twisted and pulled along the eyebrows to remove a row of hairs at a time. It provides a precise shape and removes hair more effectively than other methods like tweezing. It causes less skin irritation and has benefits like slower regrowth and thinner hair over time.